Tap Assist is an accessibility feature that turns an iPad into an adaptive input device. It helps users with mobility impairment use any app by providing larger tap targets and support for gestures like swiping that may be difficult to execute with precision.

Motor Accessibility

In designing for accessibility, we often focus on visual and audio accessibility, but less frequently on mobility. Existing options for users with limited mobility include alternative methods of navigation and input, such as voice-control. Another category of assistive technology uses external input devices, like sip-and-puff sensors and external switches.

Images from XBox adaptive controller and Craig Univeristy.

iOS’s existing, built-in Switch Control utility allows these external buttons to be connected to an iOS device and used as tap targets to interact with apps. But complicated device setups can be expensive and inflexible, both in the physical mounting they require and in their fixed assignment, which can be cumbersome to customize on the fly.

A native utility

By using the extra screen space of an iPad to present larger tap targets, disabled users can get the benefit of adaptive switches without connecting additional gear. As a native utility, that is, a tool built into the operating system itself, Tap Assist can leverage the system's visual patterns and navigation models. Here's a demo of Tap Assist navigating through the items on a home screen - the blue highlight and navigational structure are preexisting elements in iOS, but the layout and large tap targets are unique to Tap Assist.

This video shows a simple configuration with forward and back tap targets, a primary switch for activating the selected element, and a ⌘ command to open a menu of advanced gestures. By default, iOS treats rows of apps as groups that can be entered and exited, and the logic of navigation is baked into iOS's accessibility features. As such, Tap Assist is not a revolutionary approach so much as it is a stragic leveraging of iOS's adaptive tools and the inherent accessibility of a large touch screen.

Specifically, the large digital display allows controls to be customized and context-aware. In this example, Tap Assist recognizes the selected element as a slider and displays a large swipe target.

Current Switch Control users are able to enter a custom menu of gestures that accommodate advanced gestures, but these actions take many steps to complete. Apps like Instagram that depend heavily on gesture experimentation to discover features are often inaccessible.

In the next example, Tap Assist presents a joystick control when the selected element is draggable. By giving users a bigger target area and the ability to see the object they're manipulating, Tap Assist can make a complicated task easy and precise.

Technical Considerations

The biggest drawback of designing an iOS utility is that only Apple can develop it. Replicating the functionality in a third-party app isn’t possible since one app can’t open and manipulate another. The closest prototypable approximation of the Tap Assist concept would be an app with large tap targets and a mobile-browser viewport for navigating mobile-web versions of other apps. While it’s a useful strategy for concept validation, in practice many apps don’t have equivalent web apps. And those that do rarely support full functionality and accessibility.

Design Strategy

As a native utility, Tap Assist can leverage Apple's existing patterns around accessible navigation, like its menus for gestures and visual styles for highlighting. In fact, the more Tap Assist uses preexisting patterns, the more robust and extensible it will be, and the more edge cases and unexpected scenarios it will handle gracefully.

Adaptive controls and settings built into iOS.

For example, all the icons used in the design are part of Apple's SF Symbols library preloaded into iOS. While this lends visual consistency approriate for a system-level utility, it also means that VoiceOver can naturally recognize and address the icons by their default labels. Just as identities and disabilites can intersect in ways that are more than just the sum of two conditions, using multiple adaptive technolgies can introduce new conditions and challenges. Minimalism is not just an aesthetic, but a strategic approach to managing complexity and the barriers it may unwittingly introduce.

Character development, just for fun.

But minimalist design doesn't have to be dry, and adaptive technology doesn't have to look like medical equipment. Tap Assist supports independence and dignity by removing barriers to access, but also by extending delightful user experiences to those with mobility impairment. Tap Assist is designed to be flexible and friendly - above all, Tap Assist is designed to be helpful.