The robust web application can be accessed by visiting m.google.com/voice on your mobile device and works with phones running iPhone 3.0 software and above and Palm webOS.
The new HTML5 web app includes a few extra bonuses like a sleek design for your Google Voice inbox, the option to create homescreen icons for individual pages and the ability to display your Google Voice number as the outbound caller ID so you can easily receive return calls. You can also send and receive text messages for free.
Unfortunately Google Voice is still invite-only, which means that iPhone and Palm webOS users who haven't received a Google Voice invite are still out of luck.
Google's decision to use HTML5 to circumvent Apple's app store approval process while still powering a rich application experience on the iPhone demonstrates the flexibility of HTML5 in mobile web browsers, and also highlights a growing trend in iPhone application development.
Watch the video below for a demonstration of the new Google Voice mobile web app on the iPhone.