Google Play Research WHAT YOU NEED to BUILD a KICKASS APP an Analysis of Android Apps in the Google Play Store

Google Play Research WHAT YOU NEED TO BUILD A KICKASS APP An Analysis of Android Apps in the Google Play Store

This analysis explores the following topics:

In the past decade, mobile apps have become our daily App Popularity and Rating by Category: confidants. We share with them our health concerns and What are the most interesting app categories - communication, social, family, beauty, games, etc.? rely on them to get fit. We log our calories and sleep Does the number of downloads represent popularity and engagement? habits. We rely on them for transportation of all kinds and Which app categories are users most satisfied or dissatisfied with? Which are the most popular or highest rated apps by category? we count on them to entertain us with music, books, Which are the most popular apps by rating, downloads, willingness to pay, and app size in MB? and games. What influences satisfaction ratings? Popularity (number The Google Play Store had over 82 billion app downloads in 2016 and over 2.6 million apps of installs), number of reviews, app size or others? were published in 2018 (1). Mobile apps connect our virtual life and our real life. During the last decade, the use of apps for communication, information, and entertainment has increased Will we find correlations between popular app download numbers with app ratings (the higher worldwide, changing social interactions and supporting new forms of coordination and social app popularity the higher the app rating)? connections (2). Are there less noticed apps that have a high user rating but with fewer downloads? Do they have potential to grow? On the other hand, are there popular apps with lower or fewer We examined the distribution of app categories, to what extent users are satisfied with user ratings? their apps, and whether user satisfaction correlates with popularity in terms of download. Which factors are mostly related to an app’s ratings (satisfaction)? Furthermore, this analysis points to the indicators that influence users' satisfaction with apps.

View our interactive dashboard for full visualization of the research data.

1 Methodology

We located the most intriguing ﬁrst-of-its-kind dataset on Kaggle (3) for Google Play Store Apps. In this analysis, we focused on 7,888 apps that had more than 1,000 installs 1 . Of those, 7,576 apps had a rating score. The dataset was last updated in September 2018. Current analysis on mobile apps has focused mainly on Apple Store data. However, this dataset focuses on mobile apps hosted and downloaded Content rating groups on Google Play are divided into 5 groups: from Google Play, the Android mobile app store. Everyone (6354 apps) The dataset includes the following ﬁelds: Teen (888 apps) Mature 17+ (341 apps) Everyone 10+ (306 apps) Adult only (3 apps)

App Categories Number of app installs / downloads Whether the app is via Google Play Store on Android phones paid-for or free

Size of the App (MB) App Rating Number of Reviews

1 Without duplicate apps

2 Analysis Variables

33 app categories (in alphabetical order) App rating value of category (adjusted average) ART AND DESIGN, AUTO AND VEHICLES, BEAUTY, BOOKS AND REFERENCE, BUSINESS, We multiplied the app rating with its number of reviewers and summed these results for COMICS, COMMUNICATION, DATING, EDUCATION, ENTERTAINMENT, EVENTS, FAMILY, all the apps in each category. This outcome was divided with accumulated number of all FINANCE, FOOD AND DRINK, GAME, HEALTH AND FITNESS, HOUSE AND HOME, the reviews in each category. LIBRARIES AND DEMO, MAPS AND NAVIGATION, MEDICAL, NEWS AND MAGAZINES, PARENTING, PERSONALIZATION, PHOTOGRAPHY, PRODUCTIVITY, SHOPPING, SOCIAL, App rating rank (the lower the value, the higher rank, where 1= very high 2 ) SPORTS, TOOLS, TRAVEL AND LOCAL, VIDEO PLAYERS and WEATHER. 1. The app rating value 2. The number of reviews 13 app install groups If 2 apps had the same app rating value, the app with the higher number of reviews 13 install values with three popularity levels; received a higher rank than the other app. TOP popularity installs; 1 Billion +, 500 Million + 100 Million + MID popularity installs; 50 Million +,10 Million +, 5 Million + Apps by size (MB) LOW popularity installs; 1 Million +, 500K +, 100K+, 50K+, 10K+, 5K+, 1K+ The size of apps was between 1 MB, to 100 MB. Values with " Varies with device" App installs value in each category level (absolute value) were reduced from computing the average. This estimation value is an accumulation of all apps installs values (using the minimum value of the category) in a given category (For example, a category with 10 apps; 4 apps Paid-for vs. Free apps with 500 million installs + 3 apps of 50 million + 7 apps of 1 million installs = 2.157 Binary variable when paid-for = 1 and free = 0. billion installs of that category).

App installs index of category levels (on scale of 0-10) We divided the findings into three parts. In the first stage, we identified types of apps by category, We ranked all 33 categories from the lowest absolute value, to the highest absolute value, installs, payment type and size. In the second part, we classified the app rating by users/reviewers. and ranked them from 0 to 10. The category with a 0 value had fewer apps in the category Finally, we explored the differences in app rating by app type – Categories, Installs, Payment and very low app installs. The category with a 10 value had many apps in the category, type, and Size. and the highest absolute app installs.

2 Ranking only apps with more than 300 reviews

3 Main Findings

Number of apps: Reviews and app ratings:

Overall, the Google Play store dataset had 7,888 apps (we analyzed only apps that had more 20.9 billion reviews were given for these app installs, and a high rating was reported for the apps, than 1000 installs per app) in 33 categories of interest. The categories of apps with the highest 4.40, on scale of 1-5, when 5= very high. The top 5 app categories with the highest app ratings numbers of apps were Family (19% of all apps), Games (11% of apps), and Tools (9% of apps). are in the Medical category (4.62 rating), Education (4.60), Parenting (4.60), Health and Fitness Following these were the Finance and Productivity categories with 4% of overall apps (per each). (4.57), and Tools (4.54). At the bottom of app ratings are Libraries and Demos (4.08 rating), Dating (4.17) and Events (4.18). App installs:

These 7,888 apps had 75 billion installs via Android around the world. In the installs index (0-10, very high), we found 3 categories with a value of 10 (10=top value); Games with 13.9 billion installs (18.5% of all installs), Communication with 11 billion installs (14.6%) and Tools with 8.1 billion (10.8%). These three categories (top 10 value) constitute 44% of all app installs in 33 categories. The second level, Value 9 on the installs index, includes Productivity apps with 5.8 billion installs (7.7%), Social apps with 5.5 billion installs (7.3%), and Photography apps with 4.7 billion installs (6.2%). This index value of 9 includes 21% of all app installs out of 33 categories of interest. The categories with a 9 - 10 installs index value make up 65% of all app installs in the Google Play Store.

4 Table A: Summary of the Number of Apps, Installs, Reviews, and Ratings by Category and Segment

Number of Apps Installs Reviews Category Rating

Number % of In % of Install (Index 0-10, Number of % of Value Category Rank Segment Category of Apps Apps Millions Installs 10=very high) Reviews in Millions Reviews (Scale 1-5, 5= high) (1-33, 1=highest) B MEDICAL 252 3% 39 0.1% 1 1.29 0% 4.62 1 B EDUCATION 119 2% 353 0.5% 3 13.37 1% 4.60 2 B PARENTING 58 1% 32 0.0% 0 0.96 0% 4.60 3 A HEALTH AND FITNESS 228 3% 1,144 1.5% 6 21.37 1% 4.57 4 A TOOLS 686 9% 8,113 10.8% 10 229.59 11% 4.54 5 A PERSONALIZATION 274 3% 1,532 2.0% 6 53.54 3% 4.51 6 A BOOKS AND REFERENCE 176 2% 1,666 2.2% 7 16.72 1% 4.50 7 B AUTO AND VEHICLES 67 1% 53 0.1% 2 1.16 0% 4.49 8 B ART AND DESIGN 62 1% 114 0.2% 2 1.42 0% 4.47 9 A GAME 890 11% 13,984 18.5% 10 624.20 30% 4.45 10 A SHOPPING 173 2% 1,410 1.9% 6 44.57 2% 4.45 11 A PRODUCTIVITY 281 4% 5,798 7.7% 9 55.60 3% 4.43 12 A PHOTOGRAPHY 254 3% 4,669 6.2% 9 105.68 5% 4.43 13 B HOUSE AND HOME 67 1% 97 0.1% 2 1.93 0% 4.41 14 B WEATHER 74 1% 361 0.5% 4 12.30 1% 4.41 15 A VIDEO PLAYERS 149 2% 3,927 5.2% 8 67.49 3% 4.40 16 B MAPS AND NAVIGATION 116 1% 503 0.7% 4 17.73 1% 4.40 17 D COMICS 54 1% 45 0.1% 1 2.34 0% 4.39 18 D FOOD AND DRINK 95 1% 212 0.3% 3 6.33 0% 4.38 19 D FINANCE 294 4% 455 0.6% 4 12.66 1% 4.38 20 C FAMILY 1,534 19% 4,438 5.9% 8 143.99 7% 4.37 21 C TRAVEL AND LOCAL 189 2% 2,895 3.8% 8 26.82 1% 4.36 22

5 Table A: Summary of the Number of Apps, Installs, Reviews, and Ratings by Category and Segment

Number of Apps Installs Reviews Category Rating

Number % of In % of Install (Index 0-10, Number of % of Value Category Rank Segment Category of Apps Apps Millions Installs 10=very high) Reviews in Millions Reviews (Scale 1-5, 5= high) (1-33, 1=highest) C SPORTS 253 3% 1,096 1.5% 5 35.35 2% 4.34 23 D BEAUTY 46 1% 27 0.0% 0 0.40 0% 4.32 24 C BUSINESS 230 3% 697 0.9% 5 9.89 0% 4.32 25 C LIFESTYLE 276 3% 504 0.7% 5 11.83 1% 4.32 26 C NEWS AND MAGAZINES 205 3% 2,369 3.1% 7 23.13 1% 4.30 27 C ENTERTAINMENT 102 1% 2,114 2.8% 7 34.77 2% 4.28 28 C COMMUNICATION 245 3% 11,039 14.6% 10 285.84 14% 4.28 29 C SOCIAL 198 3% 5,488 7.3% 9 227.94 11% 4.27 30 D EVENTS 40 1% 16 0.0% 0 0.16 0% 4.18 31 D DATING 123 2% 141 0.2% 3 3.62 0% 4.17 32 D LIBRARIES AND DEMO 78 1% 53 0.1% 1 0.91 0% 4.08 33 Total 7,888 100% 75,386 100.0% 2,094.89 100% 4.40

Categories of Interest Segmentation

In this study we mapped the 33 app categories on two dimensions; app rating (on scale of 1-5, where 5= very high) and the installation index (on a scale of 0-10, where 0 = less than 100 thousand installs in the category, and 10= more than 8 billion app installs in the category) into 4 segments A, B, C, and D.

6 Table B: Map of Categories- Segmentation Installs by Rating and Install Group

Quadrant of Category by Installs and Rating B A

4.7

MEDICAL EDUCATION 4.6 HEALTH AND PARENTING FITNESS GAME PERSONALIZATION 4.5 AUTO AND VEHICLES BOOKS AND TOOLS ART AND DESIGN REFERENCE WEATHER HOUSE AND HOME SHOPPING PHOTOGRAPHY MAPS AND VIDEO PLAYERS 4.4 NAVIGATION PRODUCTIVITY COMICS FAMILY FOOD AND FINANCE TRAVEL AND LOCAL DRINK SPORTS NEWS AND MAGAZINES BUSINESS 4.3 BEAUTY COMMUNICATION LIFESTYLE Rating (1-5, 5 = very high) ENTERTAINMENT SOCIAL

4.2

EVENTS DATING

4.1

LIBRARIES AND D DEMO C 1 2 3 4 5 6 7 8 9 10 Installs (Index scale 0-10, where 10 = more than 8,000 Million)

7 Group A Group C

Categories with a high app rating (> avg. 4.40) and with high installs (> 500 million of app installs Categories with a low app rating (< avg. 4.40) and with high installs (> 500 million of app installs in the category). in the category). In this segment, users have relatively low to mid satisfaction with their apps. Although, the apps in this segment are very popular. Health and Fitness Books and References Productivity Tools Games Photography Family Travel and Local Sports Personalization Shopping Video Players Business Lifestyle News and Magazines Entertainment Communication Social On average, in this segment the apps are very popular, and the users in this segment have a high satisfaction of their apps. It won’t be surprising to ﬁnd a decrease in the installs of apps with the lower satisfaction in these categories.

Group B Group D

Categories with high app ratings (> avg. 4.40) and with low installs (< 500 million app installs in Categories with a low app rating (< avg. 4.40) and with low installs (< 500 million of app installs the category). In this segment, users also have relatively high satisfaction with their apps, but the in the category). In this segment, users had a relatively low to mid satisfaction with their apps, apps in this segment have Low to Mid installs. and the apps in this segment have Low to Mid installs.

Medical Weather Comics Food and Drink Finance Auto and Vehicles Parenting Beauty Events Dating Educations Maps and Navigation Libraries Demos

Since the satisfaction level of apps in the segment is high, it is evident that these categories have In this segment, the users are apparently expecting an improvement to apps in these categories. potential to increase app installs. Mostly, in Libraries and Demo, Dating, and Events.

8 Top App Ranking (1-50) 3

The Top 5 apps with the highest rating (and high number of reviews) are JW library (Books (less than 1M) installs (gray ranks). These "under the radar" apps have potential to increase their category), Six Pack (Health and Fitness category), Tickets PDA 2018 (Auto and Vehicles), Learn installs, due to the high levels of user satisfaction. For example, Hungry Hearts Diner (Rank 9, (Education), and Period Tracker (Medical). In the TOP 50 app rating, we found 21 apps with low Family), Solitaire (Rank 11, Game) and Down Dog – Yoga (Rank 12, Health and Fitness) (Table C).

Table C: Top Apps Ranked 1-50 (gray= apps that have less than 1M installs and a high satisfaction rating)

Rank App Rating Content Rating Reviews Installs Category 1 JW Library 4.90 Everyone 922,752 10,000,000+ BOOKS AND REFERENCE 2 Six Pack in 30 Days - Abs Workout 4.90 Everyone 272,337 10,000,000+ HEALTH AND FITNESS 3 Tickets + PDA 2018 Exam 4.90 Everyone 197,136 1,000,000+ AUTO AND VEHICLES 4 Learn Japanese, Korean, Chinese Offline & Free 4.90 Everyone 133,136 1,000,000+ EDUCATION 5 Period Tracker 4.90 Everyone 100,082 1,000,000+ MEDICAL 6 StrongLifts 5x5 Workout Gym Log & Personal Trainer 4.90 Everyone 66,791 1,000,000+ HEALTH AND FITNESS 7 PixPanda - Color by Number Pixel Art Coloring Book 4.90 Everyone 55,723 1,000,000+ FAMILY 8 ipsy: Makeup, Beauty, and Tips 4.90 Everyone 49,790 1,000,000+ BEAUTY 9 Hungry Hearts Diner: A Tale of Star-Crossed Souls 4.90 Everyone 10+ 46,253 500,000+ FAMILY 10 Lose Belly Fat in 30 Days - Flat Stomach 4.90 Everyone 38,098 5,000,000+ HEALTH AND FITNESS 11 Solitaire: Decked Out Ad Free 4.90 Everyone 37,302 500,000+ GAME 12 Down Dog: Great Yoga Anywhere 4.90 Teen 28,945 500,000+ HEALTH AND FITNESS 13 The Room: Old Sins 4.90 Everyone 21,119 100,000+ GAME 14 FC Porto 4.90 Everyone 15,883 100,000+ SPORTS 15 Tickets SDA 2018 and Exam from the State Traffic Safety Inspectorate with Drom.ru 4.90 Everyone 10,479 100,000+ AUTO AND VEHICLES 16 Be My Eyes - Helping the blind 4.90 Everyone 8,418 500,000+ LIFESTYLE 17 CDL Practice Test 2018 Edition 4.90 Everyone 7,774 100,000+ AUTO AND VEHICLES 18 DMV Permit Practice Test 2018 Edition 4.90 Everyone 6,090 100,000+ AUTO AND VEHICLES 19 EXO-L Amino for EXO Fans 4.90 Teen 5,677 50,000+ SOCIAL 20 Eddsworld Amino 4.90 Teen 3,071 10,000+ SOCIAL 21 eBoox new: Reader for fb2 epub zip books 4.90 Everyone 2,739 50,000+ BOOKS AND REFERENCE FK ½eljezniֵ arִ 4.90 Everyone 1,420 10,000+ SPORTS 22 23 Br Shafi 4.90 Everyone 1,288 10,000+ FAMILY 24 FK Crvena zvezda 4.90 Everyone 1,211 10,000+ SPORTS 25 BTS j-hope LINE Launcher theme 4.90 Everyone 934 10,000+ PERSONALIZATION 26 FREE LIVE TALK 4.90 Mature 17+ 776 5,000+ DATING 27 White Noise for Baby 4.90 Everyone 717 100,000+ PARENTING

3 apps with more than 300 reviews

9 Table C: Top Apps Ranked 1-50 (gray= apps that have less than 1M installs and a high satisfaction rating)

Rank App Rating Content Rating Reviews Installs Category 28 DQSalmaan - A fan made App 4.90 Everyone 707 10,000+ FAMILY 29 Borneo Bible, BM Bible 4.90 Everyone 659 10,000+ BOOKS AND REFERENCE 30 Official Madhuban Murli 4.90 Everyone 301 10,000+ LIFESTYLE 31 Period Tracker - Period Calendar Ovulation Tracker 4.80 Everyone 4,559,407 100,000,000+ HEALTH AND FITNESS 32 DU Recorder -“ Screen Recorder, Video Editor, Live 4.80 Everyone 2,588,730 50,000,000+ VIDEO PLAYERS 33 Eternium 4.80 Teen 1,506,783 10,000,000+ FAMILY 34 PewDiePie's Tuber Simulator 4.80 Teen 1,499,466 10,000,000+ FAMILY 35 Vlogger Go Viral - Tuber Game 4.80 Everyone 1,304,467 10,000,000+ FAMILY 36 Amino: Communities and Chats 4.80 Teen 1,264,084 10,000,000+ SOCIAL 37 Period Tracker Clue: Period and Ovulation Tracker 4.80 Everyone 570,242 10,000,000+ HEALTH AND FITNESS 38 Cash, Inc. Money Clicker Game & Business Adventure 4.80 Everyone 549,720 10,000,000+ GAME 39 Dan the Man: Action Platformer 4.80 Teen 528,550 10,000,000+ GAME 40 Fernanfloo 4.80 Everyone 10+ 526,595 10,000,000+ GAME 41 30 Day Fitness Challenge - Workout at Home 4.80 Everyone 471,036 10,000,000+ HEALTH AND FITNESS 42 Al Quran Indonesia 4.80 Everyone 445,756 10,000,000+ BOOKS AND REFERENCE 43 Home Workout - No Equipment 4.80 Everyone 432,160 10,000,000+ HEALTH AND FITNESS 44 File Manager by Xiaomi: release file storage space 4.80 Everyone 337,532 10,000,000+ TOOLS 45 Video Downloader - for Instagram Repost App 4.80 Everyone 332,623 10,000,000+ VIDEO PLAYERS 46 No. Color - Color by Number, Number Coloring 4.80 Everyone 269,194 10,000,000+ FAMILY 47 Video Player All Format 4.80 Everyone 259,003 10,000,000+ VIDEO PLAYERS 48 SoloLearn: Learn to Code for Free 4.80 Teen 256,079 1,000,000+ EDUCATION 49 Should I Answer? 4.80 Everyone 237,468 1,000,000+ COMMUNICATION 50 Wordscapes 4.80 Everyone 230,849 10,000,000+ GAME

10 Apps Distribution by Installs

Of the 7,888 apps from the dataset of the Google Play Store, 3% of the apps (233 apps) have more (Mid app installs). 25% of the apps have 500K to 1 million + installs (Low app installs) and 50% of than 100 million + installs (Top app installs), 22% of the apps have 5 Million till 50 Million + installs the apps have less than 100K + installs (Very Low app installs).

Table D: Percentage of Install Group Per Category

Category High Installs Mid Installs Low Installs Very Low Installs Number of Apps % of Apps FAMILY 1% 17% 24% 59% 1,534 19% GAME 7% 38% 25% 31% 890 11% TOOLS 4% 21% 19% 56% 686 9% FINANCE 0% 12% 25% 63% 294 4% PRODUCTIVITY 8% 25% 25% 42% 281 4% LIFESTYLE 0% 14% 22% 63% 276 3% PERSONALIZATION 3% 21% 23% 53% 274 3% PHOTOGRAPHY 7% 42% 25% 26% 254 3% SPORTS 1% 28% 23% 47% 253 3% MEDICAL 0% 1% 12% 88% 252 3% COMMUNICATION 11% 29% 21% 39% 245 3% BUSINESS 1% 14% 18% 67% 230 3% HEALTH AND FITNESS 1% 24% 37% 39% 228 3% NEWS AND MAGAZINES 1% 17% 26% 56% 205 3% SOCIAL 7% 27% 24% 42% 198 3% TRAVEL AND DLOCAL 3% 26% 25% 46% 189 2% BOOKS AND REFERENCE 3% 16% 20% 61% 176 2% SHOPPING 3% 39% 30% 28% 173 2% VIDEO PLAYERS 6% 28% 25% 41% 149 2% DATING 0% 11% 30% 59% 123 2% EDUCATION 1% 23% 48% 29% 119 2% MAPS AND NAVIGATION 2% 23% 24% 51% 116 1% ENTERTAINMENT 6% 43% 38% 13% 102 1% FOOD AND DRINK 0% 24% 35% 41% 95 1% LIBRARIES AND DEMO 0% 6% 18% 76% 78 1% WEATHER 0% 28% 38% 34% 74 1% AUTO AND VEHICLES 0% 7% 27% 66% 67 1% HOUSE AND HOME 0% 13% 45% 42% 67 1% ART AND DESIGN 0% 13% 16% 71% 62 1% PARENTING 0% 3% 28% 69% 58 1% COMICS 0% 9% 30% 61% 54 1% BEAUTY 0% 4% 30% 65% 46 1% EVENTS 0% 5% 13% 83% 40 1% Total 3% 22% 25% 50% 7,888 100% 11 Top Installed Apps Low Installed Apps

Of the most installed apps, with 1 billion + installs, we ﬁnd 20 apps. The highest rated apps are Finally, of the Low app installs, with 1 million + installs, the top rated apps are Tickets + PDA Instagram (4.50 rating, with the "Teen" content rating group giving a high rating to this Social 2018 Exam (Auto and Vehicle), Learn Japanese, Korean, Chinese (Education), Period Tracker category), Subway Surfers (4.50 rating, with the "everyone 10+" content rating group rating this Game (another medical app), Strong Lifts 5x5 Workout Gym Log (Health and Fitness), PixPanda (Family) category), and Google Photos (4.50 rating, with the "everyone" content rating group rating the and ipsy: Makeup (Beauty category). Photography category). Facebook ranks only 14 (4.10 rating, with the content rating group “Teen” rating this Social category). In the second level of Low app installs, with 500,000+ installs, the top rated apps are Hungry Hearts Diner (Family), Solitaire (Game), Down Dog: Great Yoga Anywhere (Health and Fitness) In the second level of highly installed apps - 500 million + installs, the highest rated apps are Clean and Be My Eyes - Helping the blind (Lifestyle). Master (Tools category), Security Master – Antivirus (Tools), SHAREit - Transfer & Share (Tools) and Google Duo (Communication). Of the apps with less than 100,000+ installs are The Room: Old Sins (Game), FC Porto (Sports) Finally, in the top installs of 100 million +, the highest rated apps are Period Tracker - Period and Tickets SDA 2018 (Auto and Vehicle). Calendar Ovulation Tracker (Health and Fitness), Piano Tiles (Game), Duolingo (Education), Bible (Books) and Booking.com (Travel and Local). Also, the apps with high ratings in the Mid and Low installs segment have potential to grow their install numbers. Mid Installed Apps

Of these apps, with 50 million + installs, the top rated apps are DU Recorder (Video Player), Mercado Libre (Shopping), Kaspersky (Tools) and Video Editor (Photography).

Of the apps with 10 million + installs, the top rated apps are JW Library (Books), and Six Pack in 30 Days (Health and Fitness).

The top rated apps with 5 million + installs are Lose Belly Fat in 30 Days (Health and Fitness) and Fines of the State Traﬃc (Auto and Vehicle).

12 Table E: Top Apps by High, Mid, and Low Install Groups

Top Apps within High Install Groups (> 1 BN + Installs)

App Content App Content App Content App Install Group= >1BN Rating Rating # of Reviews Category App Install Group= >500M Rating Rating # of Reviews Category App Install Group= >100M Rating Rating # of Reviews Category 1 Instagram 4.50 Teen 66,577,446 SOCIAL 1 Clean Master 4.70 Everyone 42,916,526 TOOLS 1 Period Tracker - Period... 4.80 Everyone 4,559,407 HEALTH AND FITNESS 2 Subway Surfers 4.50 Everyone 10+ 27,725,352 GAME 2 Security Master - Antivirus 4.70 Everyone 24,900,999 TOOLS 2 Piano Tiles 4.70 Everyone 8,118,880 GAME 3 Google Photos 4.50 Everyone 10,859,051 PHOTOGRAPHY 3 SHAREit - Transfer & Share 4.60 Everyone 7,790,693 TOOLS 3 Duolingo: Learn Languages 4.70 Everyone 6,297,590 EDUCATION 4 WhatsApp Messenger 4.40 Everyone 69,119,316 COMMUNICATION 4 Google Duo - High Quality... 4.60 Everyone 2,083,237 COMMUNICATION 4 Bible 4.70 Teen 2,440,695 BOOKS AND REFERENCE 5 Google 4.40 Everyone 8,033,493 TOOLS 5 UC Browser - Fast Download 4.50 Teen 17,714,850 COMMUNICATION 5 Booking.com 4.70 Everyone 1,830,388 TRAVEL AND LOCAL 6 Google Drive 4.40 Everyone 2,731,211 PRODUCTIVITY 6 My Talking Tom 4.50 Everyone 14,892,469 GAME 6 Clash of Clans 4.60 Everyone 10+ 44,893,888 GAME 7 YouTube 4.30 Teen 25,655,305 VIDEO PLAYERS 7 MX Player 4.50 Everyone 6,474,672 VIDEO PLAYERS 7 Clash Royale 4.60 Everyone 10+ 23,136,735 GAME 8 Google Chrome: 4.30 Everyone 9,643,041 COMMUNICATION 8 Microsoft Word 4.50 Everyone 2,084,126 PRODUCTIVITY 8 360 Security 4.60 Everyone 16,771,865 TOOLS 9 Maps - Navigate & Explore 4.30 Everyone 9,235,373 TRAVEL AND LOCAL 9 Candy Crush Saga 4.40 Everyone 22,430,188 GAME 9 Shadow Fight 2 4.60 Everyone 10+ 10,981,850 GAME 10 Google Play Games 4.30 Teen 7,168,735 ENTERTAINMENT 10 Google Translate 4.40 Everyone 5,745,093 TOOLS 10 Dream League Soccer 2018 4.60 Everyone 9,883,806 GAME 11 Gmail 4.30 Everyone 4,604,483 COMMUNICATION 11 Dropbox 4.40 Everyone 1,861,310 PRODUCTIVITY 11 VivaVideo 4.60 Teen 9,879,473 VIDEO PLAYERS 12 Google+ 4.20 Teen 4,831,125 SOCIAL 12 Flipboard: News For Our Time 4.40 Everyone 10+ 1,284,018 NEWS AND MAGAZINES 12 Sniper 3D Gun Shooter 4.60 Mature 17+ 7,674,252 GAME 13 Google Street View 4.20 Everyone 2,129,707 TRAVEL AND LOCAL 13 Twitter 4.30 Mature 17+ 11,667,403 NEWS AND MAGAZINES 13 PhotoGrid 4.60 Everyone 7,529,865 PHOTOGRAPHY 14 Facebook 4.10 Teen 78,158,306 SOCIAL 14 Viber Messenger 4.30 Everyone 11,335,481 COMMUNICATION 14 Waze 4.60 Everyone 7,232,629 MAPS AND NAVIGATION 15 Skype 4.10 Everyone 10,484,169 COMMUNICATION 15 Pou 4.30 Everyone 10,486,018 GAME 15 CM Launcher 3D 4.60 Teen 6,702,776 PERSONALIZATION 16 Messenger 4.00 Everyone 56,646,578 COMMUNICATION 16 Facebook Lite 4.30 Teen 8,606,259 SOCIAL 16 ZEDGE Ringtones & Wallpa... 4.60 Teen 6,466,641 PERSONALIZATION 17 Hangouts 4.00 Everyone 3,419,513 COMMUNICATION 17 Temple Run 2 4.30 Everyone 8,119,154 GAME 17 AliExpress 4.60 Teen 5,917,485 SHOPPING 18 Google Play Books 3.90 Teen 1,433,233 BOOKS AND REFERENCE 18 imo free video calls and chat 4.30 Everyone 4,785,988 COMMUNICATION 18 Score! Hero 4.60 Everyone 5,419,676 GAME 19 Google News 3.90 Teen 878,065 NEWS AND MAGAZINES 19 Samsung Health 4.30 Everyone 480,208 HEALTH AND FITNESS 19 ES File Explorer File Manager 4.60 Everyone 5,383,985 PRODUCTIVITY 20 Google Play Movies & TV 3.70 Teen 906,384 VIDEO PLAYERS 20 LINE: Free Calls & Messages 4.20 Everyone 10,790,289 COMMUNICATION 20 Pinterest 4.60 Teen 4,305,441 SOCIAL 21 Gboard - the Google Keyboard 4.20 Everyone 1,859,115 TOOLS 21 VideoShow 4.60 Everyone 4,016,834 VIDEO PLAYERS 22 Google Calendar 4.20 Everyone 858,230 PRODUCTIVITY 22 Angry Birds 2 4.60 Everyone 3,883,589 GAME 23 Cloud Print 4.10 Everyone 282,460 PRODUCTIVITY 23 YouCam Makeup 4.60 Everyone 3,337,956 PHOTOGRAPHY 24 Snapchat 4.00 Teen 17,015,352 SOCIAL 24 CM Locker 4.60 Everyone 3,090,727 TOOLS 25 Parallel Space 4.60 Everyone 3,062,845 PERSONALIZATION 26 Wattpad – Free Books 4.60 Teen 2,915,189 BOOKS AND REFERENCE 27 Hill Climb Racing 2 4.60 Everyone 2,750,645 GAME 28 Talking Tom Gold Run 4.60 Everyone 2,698,889 GAME 29 ColorNote Notepad Notes 4.60 Everyone 2,401,017 PRODUCTIVITY 30 Backgrounds HD (Wallpapers) 4.60 Teen 2,390,185 PERSONALIZATION 31 Bitmoji 4.60 Teen 2,312,084 FAMILY 32 CamScanner 4.60 Everyone 1,502,622 PRODUCTIVITY

13 Top Apps within Mid Install Groups (> 50 M + and up to 500 M + Installs)

App Content App Content App Content App Install Group= >50M Rating Rating # of Reviews Category App Install Group= >10M Rating Rating # of Reviews Category App Install Group= >5M Rating Rating # of Reviews Category 1 DU Recorder 4.80 Everyone 2,588,730 VIDEO PLAYERS 1 JW Library 4.90 Everyone 922,752 BOOKS AND REFERENCE 1 Lose Belly Fat in 30 Days 4.90 Everyone 38,098 HEALTH AND FITNESS 2 Mercado Libre 4.70 Everyone 3,860,225 SHOPPING 2 Six Pack in 30 Days 4.90 Everyone 272,337 HEALTH AND FITNESS 2 Fines of the State Traffic 4.80 Everyone 116,986 AUTO AND VEHICLES 3 Kaspersky 4.70 Everyone 2,598,579 TOOLS 3 Eternium 4.80 Teen 1,506,783 FAMILY 3 Fame Boom for Real Followers 4.70 Everyone 896,118 SOCIAL 4 Video Editor 4.70 Everyone 2,163,282 PHOTOGRAPHY 4 PewDiePie's Tuber Simulator 4.80 Teen 1,499,466 FAMILY 4 Egg, Inc. 4.70 Everyone 580,160 FAMILY 5 Toy Blast 4.70 Everyone 1,889,582 GAME 5 Vlogger Go Viral 4.80 Everyone 1,304,467 FAMILY 5 Cytus 4.70 Everyone 541,732 GAME 6 Bubble 4.70 Everyone 1,732,263 GAME 6 Amino: 4.80 Teen 1,264,084 SOCIAL 6 Darkness Rises 4.70 Teen 456,474 FAMILY 7 CATS: 4.70 Everyone 1,559,650 GAME 7 Period Tracker Clue: 4.80 Everyone 570,242 HEALTH AND FITNESS 7 English with Lingualeo 4.70 Everyone 254,519 EDUCATION 8 Bowmasters 4.70 Teen 1,536,349 GAME 8 Cash, Inc. 4.80 Everyone 549,720 GAME 8 To Do List 4.70 Everyone 253,155 PRODUCTIVITY 9 Brightest 4.70 Everyone 1,335,799 TOOLS 9 Dan the Man: 4.80 Teen 528,550 GAME 9 The Guardian 4.70 Teen 247,992 NEWS AND MAGAZINES 10 ZenUI 4.70 Everyone 1,141,545 PERSONALIZATION 10 Fernanfloo 4.80 Everyone 10+ 526,595 GAME 10 Narcos: Cartel Wars 4.70 Teen 244,797 FAMILY 11 The birth 4.70 Teen 1,084,945 SHOPPING 11 30 Day Fitness Challenge 4.80 Everyone 471,036 HEALTH AND FITNESS 11 Angry Birds Match 4.70 Everyone 227,401 FAMILY 12 Calculator 4.70 Everyone 287,250 PRODUCTIVITY 12 Al Quran Indonesia 4.80 Everyone 445,756 BOOKS AND REFERENCE 12 Anime Love Story Games 4.70 Everyone 198,480 FAMILY 13 Castle Clash: 4.60 Everyone 10+ 4,578,890 GAME 13 Home Workout 4.80 Everyone 432,160 HEALTH AND FITNESS 13 Offline Maps & Navigation 4.70 Everyone 193,364 TRAVEL AND LOCAL 14 Township 4.60 Everyone 4,451,317 FAMILY 14 File Manager 4.80 Everyone 337,532 TOOLS 14 Bingo by IGG: 4.70 Teen 183,343 GAME 15 Gardenscapes 4.60 Everyone 4,129,665 GAME 15 Video Downloader 4.80 Everyone 332,623 VIDEO PLAYERS 15 Ayat - Al Quran 4.70 Everyone 173,394 FAMILY 16 War Robots 4.60 Everyone 10+ 3,073,251 GAME 16 No. Color 4.80 Everyone 269,194 FAMILY 16 Sygic Car Navigation 4.70 Everyone 162,049 MAPS AND NAVIGATION 17 Master for Minecraft 4.60 Everyone 2,674,051 TOOLS 17 Video Player All Format 4.80 Everyone 259,003 VIDEO PLAYERS 17 My Calendar - Period Tracker 4.70 Everyone 156,410 MEDICAL 18 MARVEL Future Fight 4.60 Everyone 10+ 2,354,042 FAMILY 18 Wordscapes 4.80 Everyone 230,849 GAME 18 CALCU 4.70 Everyone 152,692 TOOLS 19 CM Browser 4.60 Everyone 2,265,084 COMMUNICATION 19 SofaScore Live Score 4.80 Everyone 221,722 SPORTS 19 Free english course 4.70 Everyone 142,632 EDUCATION 20 Clean Master Lite 4.60 Everyone 2,246,379 TOOLS 20 Lose Weight in 30 Days 4.80 Everyone 220,125 HEALTH AND FITNESS 20 Color by Number New Coloring4.70 Book Everyone 10+ 142,308 GAME 21 Twitch: Livestream 4.60 Teen 2,133,296 ENTERTAINMENT 21 Abs Workout 4.80 Everyone 69,279 HEALTH AND FITNESS 21 Evie Launcher 4.70 Everyone 139,258 PERSONALIZATION 22 Calorie Counter 4.60 Everyone 1,873,523 HEALTH AND FITNESS 22 Toon Blast 4.70 Everyone 1,351,771 GAME 22 Nubank 4.70 Everyone 130,582 FINANCE 23 Keepsafe Photo Vault: 4.60 Everyone 1,656,808 PHOTOGRAPHY 23 GO Security 4.70 Everyone 1,251,479 TOOLS 23 Clean My Android 4.70 Everyone 101,163 PRODUCTIVITY 24 Geometry Dash Meltdown 4.60 Everyone 1,591,129 GAME 24 Muslim Pro 4.70 Everyone 1,133,393 LIFESTYLE 24 U Launcher Lite 4.70 Everyone 87,510 ART AND DESIGN 25 Pic Collage 4.60 Everyone 1,451,000 PHOTOGRAPHY 25 Pixel Art: 4.70 Everyone 1,125,566 GAME 25 Content Transfer 4.70 Everyone 19,302 PRODUCTIVITY 26 Groupon 4.60 Teen 1,371,082 SHOPPING 26 Learn languages, with Memrise 4.70 Everyone 1,107,948 EDUCATION 26 FINAL FANTASY BRAVE EXVIUS 4.60 Teen 745,684 GAME 27 Earn to Die 2 4.60 Teen 1,327,269 GAME 27 Domino's Pizza USA 4.70 Everyone 1,032,935 FOOD AND DRINK 27 Castle Clash: Epic Empire ES 4.60 Everyone 10+ 584,070 FAMILY 28 Nova Launcher 4.60 Everyone 1,121,805 PERSONALIZATION 28 Zombie Catchers 4.70 Everyone 990,796 GAME 28 ETERNITY WARRIORS 2 4.60 Teen 568,391 GAME 29 LIKE 4.60 Teen 921,868 VIDEO PLAYERS 29 Onefootball 4.70 Everyone 911,995 SPORTS 29 Podcast Addict 4.60 Teen 413,999 NEWS AND MAGAZINES 30 Video Downloader for Face... 4.60 Teen 894,435 TOOLS 30 Cover Fire 4.70 Teen 725,897 GAME 30 Fire Emblem Heroes 4.60 Teen 407,694 FAMILY 31 Mail.Ru - Email App 4.60 Everyone 837,842 COMMUNICATION 31 Credit Karma 4.70 Everyone 706,618 FINANCE 31 Animal Jam - Play Wild! 4.60 Everyone 361,970 FAMILY 32 File Manager 4.60 Everyone 739,329 TOOLS 32 Quik 4.70 Everyone 696,665 VIDEO PLAYERS 32 DRAGON BALL LEGENDS 4.60 Teen 338,742 GAME

14 Top Apps with Low Install Groups (> 1 M + and up to 10 M + Installs)

App Content App Content App Content App Install Group= >1M Rating Rating # of Reviews Category App Install Group= >500K Rating Rating # of Reviews Category App Install Group= >100K Rating Rating # of Reviews Category 1 Tickets + PDA 2018 Exam 4.90 Everyone 197,136 AUTO AND VEHICLES 1 Hungry Hearts Diner: 4.90 Everyone 10+ 46,253 FAMILY 1 The Room: Old Sins 4.90 Everyone 21,119 GAME 2 Learn Japanese, Korean, Chin... 4.90 Everyone 133,136 EDUCATION 2 Solitaire: 4.90 Everyone 37,302 GAME 2 FC Porto 4.90 Everyone 15,883 SPORTS 3 Period Tracker 4.90 Everyone 100,082 MEDICAL 3 Down Dog: Great Yoga ... 4.90 Teen 28,945 HEALTH AND FITNESS 3 Tickets SDA 2018 4.90 Everyone 10,479 AUTO AND VEHICLES 4 StrongLifts 5x5 Workout... 4.90 Everyone 66,791 HEALTH AND FITNESS 4 Be My Eyes - Helping the blind 4.90 Everyone 8,418 LIFESTYLE 4 CDL Practice Test 2018 Edition 4.90 Everyone 7,774 AUTO AND VEHICLES 5 PixPanda - Color by Number... 4.90 Everyone 55,723 FAMILY 5 Al Quran 4.80 Everyone 57,400 BOOKS AND REFERENCE 5 DMV Permit Practice Test ... 4.90 Everyone 6,090 AUTO AND VEHICLES 6 ipsy: Makeup 4.90 Everyone 49,790 BEAUTY 6 Find a Way: Addictive Puzzle 4.80 Everyone 39,480 FAMILY 6 EXO-L Amino for EXO Fans 4.90 Teen 5,677 SOCIAL 7 SoloLearn: Learn to Code... 4.80 Teen 256,079 EDUCATION 7 Stop Smoking - EasyQuit free 4.80 Everyone 39,068 HEALTH AND FITNESS 7 Eddsworld Amino 4.90 Teen 3,071 SOCIAL 8 Should I Answer? 4.80 Everyone 237,468 COMMUNICATION 8 Pixyfy: coloring by number... 4.80 Everyone 22,290 FAMILY 8 eBoox new: Reader for fb2 epub4.90 zip booksEveryone 2,739 BOOKS AND REFERENCE Weather forecast 4.80 Everyone 159,455 WEATHER 9 German Listening 4.80 Everyone 18,298 FAMILY 9 FK ½eljezniֵ arִ 4.90 Everyone 1,420 SPORTS 9 10 Job Search by ZipRecruiter 4.80 Everyone 148,945 BUSINESS 10 Tickets SDA 2019 4.80 Everyone 7,021 AUTO AND VEHICLES 10 Br Shafi 4.90 Everyone 1,288 FAMILY 11 Drag'n'Boom 4.80 Everyone 10+ 133,180 GAME 11 English Grammar Test 4.80 Everyone 4,075 EDUCATION 11 FK Crvena zvezda 4.90 Everyone 1,211 SPORTS 12 Free Books 4.80 Teen 116,507 BOOKS AND REFERENCE 12 OnePlus Icon Pack 4.80 Everyone 440 PERSONALIZATION 12 BTS j-hope LINE Launcher theme 4.90 Everyone 934 PERSONALIZATION 13 FreePrints 4.80 Everyone 109,500 PHOTOGRAPHY 13 ES File Explorer/Manager PRO 4.70 Everyone 81,614 PRODUCTIVITY 13 FREE LIVE TALK 4.90 Mature 17+ 776 DATING 14 Ovia Pregnancy Tracker... 4.80 Everyone 102,858 MEDICAL 14 Profile Tracker 4.70 Teen 37,090 SOCIAL 14 White Noise for Baby 4.90 Everyone 717 PARENTING 15 Pregnancy Week By Week 4.80 Everyone 78,825 MEDICAL 15 Toca Life: City 4.70 Everyone 31,100 EDUCATION 15 DQSalmaan - A fan made App 4.90 Everyone 707 FAMILY 16 Pregnancy Calculator and ... 4.80 Everyone 69,126 MEDICAL 16 Migraine Buddy 4.70 Everyone 26,862 MEDICAL 16 Borneo Bible, BM Bible 4.90 Everyone 659 BOOKS AND REFERENCE 17 GoodRx Drug 4.80 Everyone 59,158 MEDICAL 17 GollerCepte 1903 4.70 Everyone 25,172 SPORTS 17 Official Madhuban Murli 4.90 Everyone 301 LIFESTYLE 18 Ovia Fertility 4.80 Everyone 53,747 MEDICAL 18 WhatsVPN - Unlimited Free VPN 4.70 Everyone 24,985 TOOLS 18 Day R Premium 4.80 Teen 51,068 FAMILY 19 Sleep Sounds 4.80 Everyone 51,227 HEALTH AND FITNESS 19 CoinMarketApp 4.70 Everyone 20,535 FINANCE 19 Relax Melodies P: Sleep Sounds 4.80 Everyone 19,543 HEALTH AND FITNESS 20 Sportractive 4.80 Everyone 48,276 HEALTH AND FITNESS 20 StyleSeat 4.70 Everyone 20,304 LIFESTYLE 20 KPOP Amino for K-Pop... 4.80 Teen 19,047 SOCIAL 21 Calculator with Percent (Free) 4.80 Everyone 48,211 TOOLS 21 Colorfit - Drawing & Coloring 4.70 Everyone 20,260 ART AND DESIGN 21 Weather Live Pro 4.80 Everyone 17,493 WEATHER 22 ReadEra 4.80 Everyone 47,303 BOOKS AND REFERENCE 22 NOOK App for NOOK Devices 4.70 Everyone 19,090 BOOKS AND REFERENCE 22 Kernel Manager for Franco... 4.80 Everyone 12,700 TOOLS 23 TravelPirates 4.80 Everyone 43,054 TRAVEL AND LOCAL 23 Hush - Beauty for Everyone 4.70 Everyone 18,900 BEAUTY 23 The House of Da Vinci 4.80 Everyone 12,400 FAMILY El Fal±ִ 4.80 Everyone 36,968 FAMILY 24 White Sound Pro 4.70 Everyone 16,570 HEALTH AND FITNESS 24 Even - organize your money... 4.80 Everyone 12,304 FINANCE 24 25 Calcy IV 4.80 Everyone 36,557 TOOLS 25 SDA Sabbath School Quarterly 4.70 Everyone 14,773 BOOKS AND REFERENCE 25 Fuzzy Seasons: Animal Forest 4.80 Everyone 10+ 12,137 FAMILY 26 ClanPlay 4.80 Teen 34,443 COMMUNICATION 26 Recipes Pastries and... 4.70 Everyone 14,065 FOOD AND DRINK 26 Tiny Scanner Pro: PDF Doc Scan 4.80 Everyone 10,295 BUSINESS 27 WebComics 4.80 Teen 33,783 COMICS 27 Al Mayadeen 4.70 Everyone 13,620 NEWS AND MAGAZINES 27 Alarmy (Sleep If U Can) - Pro 4.80 Everyone 10,249 LIFESTYLE 28 Prana Breath: Calm & Meditate 4.80 Everyone 31,665 HEALTH AND FITNESS 28 FUN Keyboard 4.70 Everyone 12,089 PERSONALIZATION 28 Equestria Amino for MLP 4.80 Teen 8,369 SOCIAL 29 Pedometer 4.80 Everyone 31,139 HEALTH AND FITNESS 29 Simple Habit Meditation 4.70 Everyone 11,689 HEALTH AND FITNESS 29 CT-ART 4.0 (Chess Tactics... 4.80 Everyone 8,191 GAME 30 Koran Read 4.80 Everyone 29,551 BOOKS AND REFERENCE 30 UniFi 4.70 Everyone 11,018 TOOLS 30 The first year of a baby's life 4.80 Everyone 7,505 PARENTING 31 Nature Sounds 4.80 Everyone 28,588 LIFESTYLE 31 Profile pictures for WhatsApp 4.70 Mature 17+ 10,786 PERSONALIZATION 31 Quran for All (Al-Huda Int.) 4.80 Everyone 6,696 FAMILY 32 Abs workout 4.80 Everyone 18,604 HEALTH AND FITNESS 32 DreamTrips 4.70 Teen 9,971 TRAVEL AND LOCAL 32 Rainbow - Journal & Activities 4.80 Everyone 6,668 PARENTING

15 Top Rated Apps by Category

Table F presents top rated apps ranked 1-15 (when 1=very high) for each one of the 33 categories, In the Social category, the highest rated apps are EXO-L Amino for EXO Fans (4.90), Eddsworld sorted by A-W. Ranked in green are indicators for "Under-the-Radar" apps which have potential to Amino (4.90) and Amino: Communities and Chats (4.80). These "Under- the-Radar" apps (less than increase their installs, based on high user satisfaction. 50 million installs. In segments with 500 million, 1 billion app installs) have the potential to increase install rates, based on high user satisfaction. Categories with a 10 value on the installs index Photography FreePrints Free Photos Delivered (44% of the installs) In the category, the highest rated apps are (4.80) and Video Editor Music, Cut, No Crop (4.70).

In the category of apps with the highest installs - Games - we found that the highest rated apps are Solitaire: Decked Out Ad Free (4.90 rating) and The Room: Old Sins (4.90 rating). The categories that followed this with high installs are the Communication and Tools categories. In the Table F: Top Apps within Category - Communication category, the highest rated apps are Should I Answer? (4.80), ClanPlay: Community See interactive dashboard for all 33 categories and Tools for Gamers (4.80), Fandango Movies - Times + Tickets (4.80). The highest rated apps in the Tools category are File Manager by Xiaomi (4.80), Calculator with Percent (Free) (4.80) and Calcy IV (4.80).

Categories with a 9 value on the installs index (21% of the installs)

Categories with high installs are Productivity, Social and Photography; In the Productivity category, the highest rated apps are QR Code Pro (4.80), Mobile Security & Antivirus (4.70) and All-In-One Toolbox: Cleaner, Booster, App Manager (4.70).

16 The Relationship between App Rating and Installs, Reviews, App Size, and App Payment Type

An app’s rating level is not only correlated to its number of installs (number of downloads), but also to number of app installs, the higher the app’s rating. However, high numbers of reviews and larger the number of reviewers, the app’s size and it’s type (paid-for or free). Indeed, learning about an app app size are also correlated to an app's high rating. based on the number of installs is indicative of its quality and the users' satisfaction. The higher the

Table H: Category Rating Descriptive Stats

Rank Category Min. Rating Max. Rating Avg. Rating Rating Range Rank Category Min. Rating Max. Rating Avg. Rating Rating Range 1 MEDICAL 2.30 5.00 4.62 2.70 18 COMICS 3.00 5.00 4.39 2.00 2 EDUCATION 3.50 4.90 4.60 1.40 19 FOOD AND DRINK 1.70 4.80 4.38 3.10 3 PARENTING 3.10 4.90 4.60 1.80 20 FINANCE 1.00 5.00 4.38 4.00 4 HEALTH AND FITNESS 1.40 4.90 4.57 3.50 21 FAMILY 1.00 5.00 4.37 4.00 5 TOOLS 1.40 5.00 4.54 3.60 22 TRAVEL AND LOCAL 2.20 4.80 4.36 2.60 6 PERSONALIZATION 3.10 4.90 4.51 1.80 23 SPORTS 2.40 4.90 4.34 2.50 7 BOOKS AND REFERENCE 2.70 5.00 4.50 2.30 24 BEAUTY 3.10 4.90 4.32 1.80 8 AUTO AND VEHICLES 2.10 4.90 4.49 2.80 25 BUSINESS 1.70 5.00 4.32 3.30 9 ART AND DESIGN 3.20 4.80 4.47 1.60 26 LIFESTYLE 1.60 5.00 4.32 3.40 10 GAME 1.00 4.90 4.45 3.90 27 NEWS AND MAGAZINES 1.70 5.00 4.30 3.30 11 SHOPPING 1.60 5.00 4.45 3.40 28 ENTERTAINMENT 3.00 4.70 4.28 1.70 12 PRODUCTIVITY 1.80 4.90 4.43 3.10 29 COMMUNICATION 2.20 4.80 4.28 2.60 13 PHOTOGRAPHY 2.00 4.80 4.43 2.80 30 SOCIAL 1.90 4.90 4.27 3.00 14 HOUSE AND HOME 2.80 4.80 4.41 2.00 31 EVENTS 3.70 4.90 4.18 1.20 15 WEATHER 3.30 4.80 4.41 1.50 32 DATING 1.90 5.00 4.17 3.10 16 VIDEO PLAYERS 1.80 4.80 4.40 3.00 33 LIBRARIES AND DEMO 3.10 5.00 4.08 1.90 17 MAPS AND NAVIGATION 1.90 4.90 4.40 3.00 Total 1.00 5.00 4.40 4.00

In addition, users are more satisfied with paid-for apps rather than free apps. These findings hint that if a user is interested in an app in a specific category, then the number of reviews, app size and the cost can predict its rating, and users’ future satisfaction with the app.

17 Table G: The Correlation between App Rating and Installs, Reviews, App Size, and App Payment Type

Rating

Installs .050**

Reviews .066**

App Size (in MB) .079**

Payment Type (Paid = 1, Free = 0) .057**

** Correlation is signiﬁcant at the 0.01 level (2-tailed).

18 Findings

A. Types of apps by categories of interest, installs, app size and payment type

Overall, of the 7,888 Google Play apps (with more than 1000 installs per app) in 33 categories, all apps) and Tools (9% of all apps). Following these, the Finance and Productivity app categories the app categories with the largest numbers of apps are Family (19% of all apps), Games (11% of each constitute 4% of overall apps.

Graph 1.1: Percentage of Apps per Category

19% 20%

15%

11%

10% 9%

5% 4% 4% 3% 3% 3% 3% 3% 3% 3% 3% 3% 3% 2% 2% 2% 2% 2% 2% 1% 1% 1% 1% 1% 1% 1% 1% 1% 1% 1% 1% 0%

GAME FAMILY TOOLS SPORTS SOCIAL DATING BEAUTY EVENTS FINANCE MEDICAL COMICS LIFESTYLE BUSINESS SHOPPING WEATHER REFERENCE EDUCATION PARENTING PRODUCTIVITY PHOTOGRAPHY VIDEO PLAYERS ENTERTAINMENT ART AND DESIGN COMMUNICATION FOOD AND DRINK PERSONALIZATION TRAVEL AND LOCAL HOUSE AND HOME HEALTH AND FITNESS LIBRARIES AND DEMOAUTO AND VEHICLES NEWS AND MAGAZINES BOOKS AND MAPS AND NAVIGATION * Without duplicate apps

19 App Installs via Google Play

From 7,888 apps in the Google Play Store, 3% of them (233 apps) have more than 100 million + 25% of the apps have 500K to 1 million + installs (Low app installs) and 50% of the apps have less installs (Top app installs), 22% of the apps have 5 Million to 50 Million+ installs (Mid apps installs). than 100K+ installs (Very Low app installs).

Graph 1.2: Apps Install Groups 3%

100M + Installs 22% 5M - 50M + Installs 500K - 1M + Installs Less than 100K + Installs

50%

25%

20 In the Top installs group (100 million+ installs), Games (27%), Tools (12%) and Communication (12%) Family, Tools and Games categories are also dominant in the Low and Very Low installs groups categories are very dominant. (Graphs 1.3, 1.4) In the Mid installs group (5-50 million + installs), Games (19%), Family (15%) and Tools (8%) categories are very dominant.

Graph 1.3: Percentage of Paid Apps per Category

MEDICAL (252 apps) 21% PERSONALIZATION (274 apps) 15% WEATHER (74 apps) 8% FAMILY (1,534 apps) 8% GAME (890 apps) 7% SPORTS (253 apps) 7% TOOLS (686 apps) 7% LIFESTYLE (276 apps) 6% COMMUNICATION (245 apps) 6% HEALTH AND FITNESS (228 apps) 5% PRODUCTIVITY (281 apps) 5% ART AND DESIGN (62 apps) 5% TRAVEL AND LOCAL (189 apps) 5% PHOTOGRAPHY (254 apps) 5% FINANCE (294 apps) 4% MAPS AND NAVIGATION (116 apps) 3% EDUCATION (119 apps) 3% BOOKS AND REFERENCE (176 apps) 3% VIDEO PLAYERS (149 apps) 3% BUSINESS (230 apps) 2% FOOD AND DRINK (95 apps) 2% ENTERTAINMENT (102 apps) 2% PARENTING (58 apps) 2% DATING (123 apps) 2% AUTO AND VEHICLES (67 apps) 1% SOCIAL (198 apps) 1% SHOPPING (173 apps) 1% NEWS AND MAGAZINES (205 apps) 0% 6% of all apps are paid-for. Relatively higher BEAUTY (46 apps) 0% Medical COMICS (54 apps) 0% rates of payment are in the category EVENTS (40 apps) 0% (21% of Medical category is paid- for), HOUSE AND HOME (67 apps) 0% LIBRARIES AND DEMO (78 apps) 0% Personalization (15%), Weather (8%) and All Apps (7,888 apps) 6% Family (8%).

21 On average, the size of an app is 22.9 (MB). Large size apps are found in Games (44 MB), Family (29.8 MB) and Sports (26.9). Following these are Travel and Local (25.5), Entertainment (25.0), and Health and Fitness (25.5).

Graph 1.4: Average App Size (in MB) by Category

GAME (890 apps) 43.6 FAMILY (1,534 apps) 29.8 SPORTS (253 apps) 26.9 TRAVEL AND LOCAL (189 apps) 25.5 ENTERTAINMENT (102 apps) 23.0 HEALTH AND FITNESS (228 apps) 23.0 PARENTING (58 apps) 22.4 FOOD AND DRINK (95 apps) 22.3 AUTO AND VEHICLES (67 apps) 21.3 MEDICAL (252 apps) 19.7 EDUCATION (119 apps) 19.5 FINANCE (294 apps) 18.9 SOCIAL (198 apps) 18.2 SHOPPING (173 apps) 18.0 DATING (123 apps) 17.9 LIBRARIES AND DEMO (78 apps) 17.7 MAPS AND NAVIGATION (116 apps) 17.4 LIFESTYLE (276 apps) 17.2 VIDEO PLAYERS (149 apps) 17.1 PHOTOGRAPHY (254 apps) 16.8 HOUSE AND HOME (67 apps) 16.5 COMICS (54 apps) 14.4 BEAUTY (46 apps) 14.4 EVENTS (40 apps) 14.3 BOOKS AND REFERENCE (176 apps) 14.0 COMMUNICATION (245 apps) 14.0 BUSINESS (230 apps) 13.6 WEATHER (74 apps) 13.6 NEWS AND MAGAZINES (205 apps) 13.2 ART AND DESIGN (62 apps) 12.7 4 PRODUCTIVITY (281 apps) 12.6 PERSONALIZATION (274 apps) 12.0 TOOLS (686 apps) 9.7 Total (7,888 apps) 22.9

0.0 10.0 20.0 30.0 40.0 50.0

4 Values with " Varies with device" reduced from computing the average.

22 B. App rating: The level of satisfaction from apps in Google Play Store

20.9 billion reviews were given for these app installs. 77% of app ratings were a value of 4 and rating was 4.15. When we weigh the average with the number of reviews (indication for number of higher (on a scale of 1-5, when 5=very high); 59% of reviews had a value from 4.00 to 4.50, and 18% of installs and users), the adjusted average is raised to a value of 4.40 (on scale 1-5, when 5= very high) reviews had values higher than 4.50. 20% of apps reviewed had a mid value between 3.00 and 3.90. (Graph 2.3 and Table I). And only 3% of apps reviewed had low values (less than 2.90) (Graphs 2.1 2.2). The average app

Graph 2.1: App Satisfaction Rating in Google Play Store

5 = High Rating 5.00 41 4.90 68 4.80 182 4.70 413 4.60 649 4.50 822 4.40 855 4.30 877 4.20 786 4.10 614 4.00 477 3.90 352 3.80 277 3.70 214 3.60 160 3.50 148 3.40 116 3.30 94 3.20 59 3.10 68 3.00 57 2.90 42 2.80 36 2.70 20 2.60 22 2.50 19 2.40 16 2.30 17 2.20 12 2.10 8 2.00 10 The top 5 app categories with high app ratings are 1.90 11 1.80 7 Medical (4.62 rating), Education (4.60), Parenting 1.70 5 1.60 4 (4.60), Health and Fitness (4.57), and Tools (4.54). 1.50 1 1.40 3 At the bottom of the app ratings are Libraries and 1.20 1 1 = Low Rating 1.00 3 Demo (4.08 rating), Dating (4.17) and Events (4.18). 0 100 200 300 400 500 600 700 800 900 1,000 Number of Apps

23 Graph 2.2: Category Rating

MEDICAL (1,287,102 reviews) 4.62 EDUCATION (13,373,920 reviews) 4.60 PARENTING (958,307 reviews) 4.60 HEALTH AND FITNESS (21,365,507 reviews) 4.57 TOOLS (229,586,138 reviews) 4.54 PERSONALIZATION (53,542,636 reviews) 4.51 BOOKS AND REFERENCE (16,722,693 reviews) 4.50 AUTO AND VEHICLES (1,163,572 reviews) 4.49 ART AND DESIGN (1,419,348 reviews) 4.47 GAME (624,202,386 reviews) 4.45 SHOPPING (44,572,123 reviews) 4.45 PRODUCTIVITY (55,598,731 reviews) 4.43 PHOTOGRAPHY (105,678,495 reviews) 4.43 HOUSE AND HOME (1,929,900 reviews) 4.41 WEATHER (12,295,220 reviews) 4.41 VIDEO PLAYERS (67,485,889 reviews) 4.40 MAPS AND NAVIGATION (17,729,031 reviews) 4.40 COMICS (2,342,393 reviews) 4.39 FOOD AND DRINK (6,326,698 reviews) 4.38 FINANCE (12,662,758 reviews) 4.38 FAMILY (143,990,365 reviews) 4.37 TRAVEL AND LOCAL (26,821,253 reviews) 4.36 SPORTS (35,348,798 reviews) 4.34 BEAUTY (396,227 reviews) 4.32 BUSINESS (9,890,376 reviews) 4.32 LIFESTYLE (11,832,367 reviews) 4.32 NEWS AND MAGAZINES (23,130,375 reviews) 4.30 ENTERTAINMENT (34,768,094 reviews) 4.28 COMMUNICATION (285,841,274 reviews) 4.28 SOCIAL (227,936,074 reviews) 4.27 EVENTS (160,869 reviews) 4.18 DATING (3,623,596 reviews) 4.17 LIBRARIES AND DEMO (906,835 reviews) 4.08 ALL APPS (2,094,889,377 reviews) 4.40

3.80 3.90 4.00 4.10 4.20 4.30 4.40 4.50 4.60 4.70

24 Graph 2.3: Install Group Average Rating

Average Rating

4.50

4.39 4.40 4.38

4.33 4.30 4.30

4.23 4.22 4.22 4.20 4.17 4.15 4.12 4.10 4.06 4.05 4.04 4.02 4.00

3.90

3.80 >1BN >500M >100M >50M >10M >5M >1M >500K >100K >50K >10K >5K >1K Total Install Group

25 Table I: Install Group Ratings Descriptive Stats

Install Group Number of Apps Min. Rating Max. Rating Average Rating Rating Range

>1BN 20 3.70 4.50 4.22 0.80 >500M 24 4.00 4.70 4.38 0.70 >100M 189 3.50 4.80 4.39 1.30 >50M 204 3.10 4.80 4.33 1.70 >10M 941 3.00 4.90 4.30 1.90 >5M 611 2.00 4.90 4.23 2.90 >1M 1418 2.20 4.90 4.22 2.70 >500K 504 1.80 4.90 4.17 3.10 >100K 1098 1.60 4.90 4.12 3.30 >50K 457 1.60 4.90 4.05 3.30 >10K 988 1.70 5.00 4.04 3.30 >5K 425 1.40 5.00 4.02 3.60 >1K 697 1.00 5.00 4.06 4.00 Total 7576 1.00 5.00 4.15 4.00

26 In general, we ﬁnd that the higher the number of app installs, the higher the app's size. And if an app is paid-for, the higher the app's rating will be (see also correlation analysis).

Graph 2.4: Average App Rating by Size (MB) Table J: App Rating by Size (in MB) Descriptive Stats

57.00 - 100.00 (630 apps) 4.25 Size Range Number Min. Max. Average Rating 39.00 - 56.00 (646 apps) 4.18 (in MB) of Apps Rating Rating Rating Range

28.00 - 38.00 (667 apps) 4.11 57.00 - 100.00 659 1.90 5.00 4.25 3.10 21.00 - 27.00 (645 apps) 4.18 39.00 - 56.00 643 2.30 4.90 4.18 2.60 15.00 - 20.00 (651 apps) 4.15 28.00 - 38.00 620 1.60 5.00 4.11 3.40 10.00 - 14.00 (646 apps) 4.17 21.00 - 27.00 652 1.00 5.00 4.18 4.00 7.00 - 9.90 (652 apps) 4.13 15.00 - 20.00 646 1.60 5.00 4.15 3.40 4.60 - 6.90 (620 apps) 4.12 10.00 - 14.00 651 1.40 5.00 4.17 3.60 3.00 - 4.50 (643 apps) 4.17 7.00 - 9.90 645 1.00 5.00 4.13 4.00 1.00 - 2.90 (659 apps) 4.00 4.60 - 6.90 667 1.00 5.00 4.12 4.00 3.00 - 4.50 646 1.40 5.00 4.17 3.60 Total (6,459 apps) 4.15 1.00 - 2.90 630 1.60 5.00 4.00 3.40 3.85 3.90 3.95 4.00 4.05 4.10 4.15 4.20 4.25 4.30 6,459 1.00 5.00 4.15 4.00

27 Graph 2.5: Free/Paid Average App Rating by Category (Top 7)

4.50 4.47

4.41 4.40 4.34 4.33 4.31 4.30 4.28 4.23 4.23 4.22 4.20 4.20 4.15 4.14

4.10

4.09 4.04 4.00

3.90

3.80 Free Paid Free Paid Free Paid Free Paid Free Paid Free Paid Free Paid MEDICAL PERSONALIZATION WEATHER FAMILY GAME SPORTS TOOLS

28 C. The Relationship between apps’ ratings with installs, reviews, app size, and app type

When analyzing the correlation between app rating and installs, reviews, app size, and type, In addition, users were more satisfied with paid-for apps (app rating) than free apps. If users are we found that an app’s rating level is not only correlated to its installs (number of units), but interested in an app in a speciﬁc category and need to choose between apps in the same install also to the number of reviewers, app size and type (paid-for or free). Indeed, crowdsourcing via group, factors such as the number of reviews, app size, and payment type predict its rating and the number of installs is an indicator of success and users' satisfaction. The higher the number of future user satisfaction levels.. app installs, the higher the app’s rating. However, high number of reviews and larger app size also correlate to a higher app rating. (Table K).

Table K: The Correlation between App Rating and Installs, Reviews, App Size, and App Payment Type

1 2 3 4 5 Rating Installs Reviews Apps Size in MB Payment Type 1 Rating (1-5, 5= very high) 1 2 Installs .050** 1 3 Reviews .066** .624** 1 4 Apps Size (in MB) .079** .128** .180** 1 5 Payment Type (Paid=1, Free=0) .057** -.040** -.031** 0.009 1

** Correlation is signiﬁcant at the 0.01 level (2-tailed).

References: 1. "Number of Google Play Store apps 2017 | Statistic". Statista. Retrieved 2018-01-03. 2. Arie, Yossef, and Gustavo S. Mesch. "The spatial and social network dimensions of mobile communication: a test of the Social Stratiﬁcation and Social Diversiﬁcation Hypotheses." Communication Research 43.5 (2016): 713-734. 3. https://www.kaggle.com/lava18/google-play-store-apps/version/5

29 Summary

The proliferation of apps and the billions of downloads For example, we’ve learned that paid apps, which may not necessarily generate the highest number of downloads, are highly ranked and appreciated. What this means is that they don’t need to be free prove that mobile apps are now a signiﬁcant part of our or have the most users to be eﬀective. The conclusion we reach is that if an app targets the right lives. They’re no longer just useful “add-ons.” As end-users, audience, and meets the audience’s needs, then it’s meaningful for people, and they’re willing to pay for it. we expect an app for anything we need, and for every product, service, and brand with which we interact. The segmentation by category, rank, install numbers, and reviews has enabled us to gain fresh insights into what engages users and where the opportunities are for businesses looking to develop This presents huge opportunities for businesses to engage customers, to develop a dialogue with new apps. By shedding light on which of these criteria are most influential, we gain instructive them, and to nurture relationships with them that create loyalty. The challenge is to understand how insights on which categories are best for growth, how to extend relationships with customers, to achieve this and how to take full advantage of these opportunities. That’s where good analysis helps. and how to maximize the success of your app.

With the massive numbers involved, it can be difficult to see the forest for the trees when trying to measure and establish the criteria for apps’ effectiveness. As the market for apps has escalated and matured, it’s no longer sufficient to identify successful apps based simply on the number of downloads. There are apps and categories of apps that lend themselves particularly well to mobile use, such as health apps, those connected to medical devices and wearables. But, apps of these kinds sometimes target specific, niche markets or user groups. Consequently, the number of users is too crude a measurement with which to judge them, and it’s this situation that has given rise to our analysis.

We realized that what was necessary was a more segmented, nuanced analysis of apps, their eﬀectiveness, and users’ satisfaction levels. That’s why the analysis of these apps in the Google Play Store extends beyond identifying individual apps and instead examines a range of considerations View our interactive dashboard such as install numbers, ranking, reviews, and category. It generates a more accurate picture of how for full visualization of the research data. businesses can make their apps work best for them and their customers.