ChromeVox: built-in spoken feedback for Chrome OS

By T.V. Raman, Research Scientist

Cross-posted with the Chromium Blog

We recently unveiled ChromeVox — a built-in screen reader for Chrome OS — during Google I/O 2011. This is an early developer beta that is designed to help authors of web applications come up to speed with platform accessibility on Chrome OS.

ChromeVox is built as a Chrome extension. This means that unlike most accessibility software, it is built using only web technologies like HTML5, CSS and Javascript. As the built-in accessibility solution for Chrome OS, it can help users with special needs access modern web apps, including those that utilize W3C ARIA (Access to Rich Internet Applications) to provide a rich, desktop-like experience.

ChromeVox leverages two of Chrome's experimental extension APIs, the experimental.tts API for cross-platform text-to-speech, and the experimental.accessibility API that lets an extension listen for accessibility events in Chrome's menus and toolbars. In turn, ChromeVox exposes a simple screen reader API to web developers who want to further customize the ChromeVox user experience. Thus, within your application, you can:

• Automatically generate spoken messages and earcons.
• Set ChromeVox to synchronize with your application's current focus.

ChromeVox also comes with an interactive online tutorial that demonstrates how users of spoken feedback interact with webpages. Examples range from static content to interactive applications. You can test these same navigation techniques within your own applications to quickly verify users can reach all portions of your application using the keyboard and obtain meaningful feedback. You can then annotate your application with the necessary ARIA properties and other accessibility enhancements to ensure that blind and visually impaired users gain complete access to your application. Please see our Google I/O 2011 talk for more.

Details on enabling accessibility in Chrome OS can be found on the Accessibility help page, and the Chrome extension is available for download from our Wiki page. For now, ChromeVox is targeted at end-users on Chrome OS, but it may also prove a useful tool to web developers using Chrome on all major platforms. We welcome your feedback via our Open Source project website at http://google-axs-chrome.googlecode.com.


T. V. Raman is a research scientist at Google. He leads a team of engineers building innovative user interfaces on Android and Chrome OS, and researches creating highly efficient eyes-free interfaces.

Posted by Scott Knaster, Editor