Using VoiceOver for Low-Cost Accessibility Testing
Mac OS X's VoiceOver application is an excellent resource for anyone who designs websites for visually impaired users. At its core, VoiceOver is a screenreader: it speaks aloud the content of a site and provides enhanced controls for keyboard navigation. Simple. Did I mention it's free and you Mac folks already have it installed?
Why should I use this?
Table-less layouts and semantic markup have created a foundation for improving accessibility. Together with automated testing tools like WebAIM WAVE and the Firefox Accessibility Toolbar, we can pinpoint common issues that can be objectively tested.
However, these tools can't tell us subjectively whether the site is usable. For example, they can't answer questions like:
- Can I easily determine where I am, whether this page will be useful, and where I can go if not?
- Is the page architecture clear and sensible? Does it hold up when the content is linearized? Does it need additional cues or landmarks?
- Does the design imply relationships that aren't communicated non-visually?
- How much cognitive load am I imposing? Is it so complex that users will have trouble "caching" it in their minds?
- Does the structure expedite or inhibit keyboard-surfers' speed?
VoiceOver helps fill this gap. By interacting with a site using a screenreader, you're better able to sense these issues. And if you're in a situation where in-person testing isn't possible, VoiceOver is a great tool at your disposal. Just cover up your screen and see if you can accomplish your users' core tasks.
The best way to understand VoiceOver is to use it. Go to System Preferences > Universal Access > VoiceOver and toggle it on. Those of you that are risk averse, rejoice! Here's a brief video that helps you get acquainted.