I found an article that explains how to make videos of your Android app in action. You can use these videos for promoting your app. See “How To Record Your Android Device’s Screen“.
It is very easy to do. All you have to do is use the ADB (Android Debug Bridge) tool in Eclipse. Connect your device and then start the ADB shell with something like this:
adb shell screenrecord /sdcard/adb_movies/m1.mp4
Once you start it, it records whatever you do on your device. Stop the recording by typing Ctrl-C. It then saves an mp4 file.
I tried it out on my Double Star game app, which is currently under development. Here is one of the demo videos that I made: