Touchscreen Use and Accessibility Issues
Touchscreens are becoming ubiquitous in mobile devices: tablets, smartphones, e-readers, etc. However, individuals who have either visual or dexterity disabilities (or both) may have difficulties using standard touchscreen technology. This article covers the types of problems that people may experience, as well as innovations that attempt to address these barriers.
Traditional touchscreen use, like mouse use, requires good hand/eye coordination. If users cannot see the target, they cannot activate it. This affects opening applications, using the virtual keyboard, and most other touch screen functions. Recent touchscreens have built-in solutions for this problem:
- The VoiceOver screen reader included in all iOS products (iPhone, iPad, iTouch) includes a sophisticated set of commands for navigating and selecting onscreen items. When VoiceOver is active, it replaces some standard iOS commands; e.g., flicking a finger left or right selects the next item rather than moving to a different page.
- VoiceOver's Rotor Control feature allows the user to set preferences for the application or environment they’re currently using. The Rotor Control requires precise movement and possible twisting of the wrist depending on which fingers are used, which may prove difficult for some users.
- Mobile Accessibility is the Android equivalent of VoiceOver. A major feature unique to Mobile Accessibility is that navigating the virtual keyboard provides tactile (vibrating) as well as audio feedback.
- Many apps run on both tablet-sized devices and smaller devices, such as smart phones. On the tablets, users often have the option of seeing the app displayed at the same size as it appears on the smaller device, or enlarged to fill the tablet screen. This may make the app more usable by people with low vision.
- Most mobile devices have a “pinching” gesture that allows users to easily enlarge or decrease text and image size on the fly.
People with dexterity disabilities may have problems with one or both of the following touchscreen functions:
- Gesturing: The pinching function described above is a typical example of gestures used with mobile technologies. The user may not be able to effectively move proximate fingers to execute these gestures.
- Pressing: Users may have difficulty pressing hard or accurately enough to interact with virtual keyboards or with tapping functions (e.g., to open a file).
- Some cases have a built-in stand so the device can be used at an angle rather than flat. This may be easier for some individuals to reach.
- Most mobile devices can be operated via external physical keyboards. Users who can operate a keyboard but not a touch screen may be able to use these for input.
- Most multi-finger iPad commands can be executed using any combination of fingers or thumbs from either hand, which benefits users who are missing or missing use of some digits.
- Mobile Accessibility includes a voice recognition component, and there is a free version of Dragon Dictate available for iOS devices. However, these are only for dictating text (replacing the virtual keyboard) not for navigation or other system functions (replacing tapping). Version 5 of the iOS operating system includes a full-featured speech recognition features for control as well as dictation.