On DZone.com there's a recent post from Giorgio Sironi looking at running Selenium tests on the Android platform via the PHPUnit Selenium interface.

Testing web applications is not only based on unit and functional tests for the server-side (PHP, Java) and client-side (JavaScript) components, but also on end-to-end tests like the ones performed with Selenium. Selenium is capable of driving a real browser like Firefox in the same way a user would do, letting you express a test with a series of page to load, element selections, clicks and typed characters. [...] In this tutorial, we'll experiment with the Android Driver and set up a couple of tests to run inside an Android virtual device.

He walks you through the basic setup of an Android environment (based on the Android SDK) and how to start up the Android driver installed from the Selenium site. An example test is included, showing how to make a request for a test page and checking its title as well as checking that the input from the "keyboard" is successful.