Experiences of QWERTY development Teemu TOROPAINEN and Pasi OJALA Oulu, Finland ABSTRACT good, usable QWERTY layout can be very challenging containing several compromises with the number and size of the keys. During the last decades researchers and industry have published several studies on QWERTY based text input technologies. Many As QWERTY keyboard seems to be “the standard keyboard” also studies have been made about mini-QWERTY and other reduced for mobile devices, this paper concentrates only on the existing QWERTY layouts targeted for mobile devices, but usually only QWERTY based layouts for mobile devices. This has been seen English language is used in these studies as input language. Also, justified because the understanding of the challenges that are faced there does not seem to be a wide consensus of which kind of when selecting QWERTY layout is clearly needed for developing layouts are most recommended for mobile devices. Selecting the layout that supports most languages and fits small enough space right QWERTY layout is even more challenging if we take into with usable key size. For these reasons we have not seen it consideration the number of supported languages versus the necessary to focus on the QWERTY key shapes and materials or number and the size of the QWERTY keys. software enablers like predictive text input or similar either. We have also seen that on-screen QWERTY is out of scope in relation This paper reviews existing QWERTY layouts for mobile devices to our research problem. and presents constructive critique for using them. Even some critique is presented it is notified that developing QWERTY layouts to mobile devices is always some sort of a compromise. 2. QWERTY IN MOBILE DEVICES Keeping this in mind this paper proposes methods to make the QWERTY smaller and still usable with multiple different languages. The placements of the keys in mini-QWERTY layouts usually follow those used in traditional QWERTY keyboards, except some The practical industrial case shows that neither of the tested variation required by certain languages (AZERTY used in French QWERTY layouts was perfect. However, a layout containing and QWERTZ used in German for example). All the keys that are characteristics of both layouts is usable for mobile devices. The used in traditional computer QWERTY keyboards are not needed case also shows the practical challenges which are often faced by in mobile devices, so mini-QWERTY layouts are usually mini-QWERTY developers and finally proposes how these somewhat simpler. In practice, mini-QWERTY typically consists challenges could be solved. of alphanumeric, special character, modifier, Space, Backspace and Enter keys. Keywords: software, QWERTY, mini-QWERTY, text input method, mobile device, usability The total amount of needed alphanumeric keys depends heavily on language. [1] If a language uses another script than Latin, e.g. Cyrillic or Arabic, both Latin and the main script are printed on the keyboard layout to enable text input in both scripts. If there is 1. INTRODUCTION more than just one language on the layout, it means that there is less space for printing characters on physical keyboards. QWERTY keyboard is well over one century old invention. Even if it is a rather old invention it can still be called as “the standard All languages have the same set of Latin number keys available: 0 of the keyboards.”[7] It has also achieved a standard role in ISO 1 2 3 4 5 6 7 8 9. Full size QWERTY has usually independent (ISO/IEC 9995, 1994). A miniature version of QWERTY (mini- number keys but in mini-QWERTY layouts the number keys are in QWERTY) [2] has been developed for mobile devices. many cases “integrated” to alphabetic keys and modifier key is Technically, mini-QWERTY must fit into a much smaller space needed for entering them. The number keys can be placed in row than the traditional QWERTY. In practice mini-QWERTY is on the top level of the QWERTY but based on our usability test usually used with two thumbs. findings presented in chapter 4 in some cases also grid layout can be a good idea since it might help input of phone numbers for Mobile devices set several limitations on the number and the size example. Especially if one-hand usage is important, grid layout of of the keys used in mini-QWERTY. In addition, many of these numbers can be recommended. keys have often multiple functions which normally cause usability problems. Especially regarding to multimedia device development The list of special characters is more or less the same for all these challenges have been seen significant. This is perhaps languages. In practice only the prioritization of the characters may because industrial design of multimedia devices starts in very early vary: phase when only the basic dimensions of the product are known. _ % * § # | , . ; : ? ! ¡ ¿ · ´ ` ~ ^ + - ’ ” ' " @ {} [] ( ) - = In addition, as the general user requirement for the mobile devices \ / & £ $ € ¥ ¤ _ <> “as small as possible”, limits the space for keyboard, designing a Modifier keys (Shift and Alt Gr for example) are typically used in Table 1. QWERTY layout used in Hwang & Lee study. combination with some alphanumeric characters to input upper case characters, special characters and accented characters. Also EQW TFY OP dead keys are considered as modifier keys in this paper because they behave in the same manner. Typically, full size QWERTY has more modifier keys than mini-QWERTY and in many cases it ADZ RGV ILJ also has more operating system specific keys. For example some keys like Enter, Backspace and Shift are often made bigger in full SCX HUB NMK size QWERTY for achieving better usability. Related work Clarkson et al. (2005) used separate mini-QWERTY devices that were attached to computer in their study. Therefore their results do not match the real mobile device environment. However, they did Green et al. (2004) have built a specialized keyboard for text entry set some kind of performance benchmark for future studies that maps four rows of a standard keyboard onto the home row, regarding input speed of mini-QWERTY devices. with different characters encoded via modifier keys and multi-tap input. Use of this keyboard relies on lexicon-based disambiguation. This kind of design has two benefits: it limits physical space requirements and capitalizes on user knowledge of the standard QWERTY keyboard layout. The resulting “stick” keyboard is between 15% and 25% of the size of a standard keyboard. In practice in a preliminary empirical study, users have reached half of their normal typing speed using lexicon-based disambiguation (22.5 wpm) and a reasonable but lower speed with multi-tap input (10.4 wpm) with only a few minutes of practicing. Figure 2. The keyboards used in Clarkson et al. (2005) study. Rennie and Cockburn (2005) did a comparative analysis and empirical evaluation of three alternative techniques for helping Figure 1. The stick keyboard used in Green et al. users input non-standard alphabets using a standard keyboard. In study. particular they investigated whether their VKPLUS (Visual Keyboard Plus) user interface, which displays both the physical Green et. al (2004) point out that each software or hardware key labels and the new key bindings, improves text entry rates innovation in text input technology must address tradeoffs between over Microsoft's Visual Keyboard. The third technique, included several issues: input speed, accuracy, physical form factor, for baseline comparison, used sticky-labels placed over the learning time and cost. Text-entry input technologies trade off physical keyboard. these factors in different ways. As result of their studies Green et. al (2004) came to the conclusion that stick keyboard will not replace devices that already require a numerical keypad, such as cell phones, or those that must be held in one hand for use. Hwang & Lee (2005) compared 3x4 QWERTY layout to traditional ABC layout in their study that was started from the hypothesis that a user's skill in a QWERTY keyboard may be Figure 3. VKPLUS: Both QWERTY characters and the transferred to a 3x4 keypad environment. They carried out two symbols to be typed in are visible on each key. experiments to find supporting evidence. The results from the first experiment suggested that the spatial memory about the QWERTY The results of Rennie and Cockburn (2005) show that VKPLUS keyboard does help the user locate correct keys. An important significantly improves performance over Microsoft's system, but implication of this was that a keypad layout that follows that of the the stickered keyboard outperformed both systems. However, it is QWERTY keyboard may be easier to learn for computer users. not a practical solution in many cases, as the stickers would Their second experiment compared the efficiency of an ABC adversely affect normal typing, it would be hard to change layout and a QWERTY-like layout and the results were clearly in alphabets, and it is not very portable. favor of the latter one. Clarkson et al. (2007) came to the conclusion that Analytic models small the keys can be from a usability point of view and a lot keys like the two-thumb model can be powerful HCI (Human Computer crammed into a small space will also look very crowded and hard Interaction) tools: predictive statements about prospective designs to read. Both of these methods must be used to achieve good have great utility. Comparing mini-QWERTY design alternatives, compromise between usability and the number of keys available. for example, this can be done at very early stages of the design process using these models. Here is a standard 62 key Finnish/Swedish QWERTY keyboard: As conclusion it seems that none of the earlier studies concentrate on how to design a mini-QWERTY that effectively supports a wide variety of languages.