If you got an iPhone or Android-powered devices and want to test Google Wave on it, there’re two ways to get Wave to work on your iPhone: First’s to go to wave.google.com using mobile Safari. Click through the warning, as it works well, as the site is optimized for Webkit-based browsers. You can select different conversation “waves” (or threads) and contacts, or dive into a specific wave. To get rid of Safari wrapper to use web apps; save a Wave bookmark on your Home screen; clicking the icon takes you to Wave, but without the Safari wrapper which allows you to navigate to another page or search the Web. Instead, it looks more like a regular app and there’s no way to navigate away from it. Everything else works the same as in the mobile browser version.
More info: Mobile blog