The ZK Framework team have released ZK Mobile for Android, an extension to ZK:
The ZK Mobile for Android is the ZK extension that enables reachness of ZK applications to Android platform mobile devices with little programming. With the event-driven components and a markup language on server side, developing is as simple as programming desktops and authoring HTML. No Android prerequisite is required.
With ZK’s server-centric architecture, developing Android application becomes a very easy task. ZK mobile developers only need to write MIL (Mobile Interactive Language) files in ZK tags without understanding Android SDK detailly. MIL is a markup language that enables developers to author a page without programming. Also, due to the tendency of server-centric framework - application runs on server, developers don’t need to re-deploy applications when applications update occurs and the business logic is controlled in server side. As soon as the application installed at the server is upgraded, the user will access the most updated version automatically. Moreover, the business logic is running at the server, so it requires much less memory in the mobile device.
With the release, they have put out a Twitter client application which you can try for yourself.