I want to do a demo just like WaveSecure, which win Android Develop Challenge 2 with a third place. Now I have a problem in locking the screen customly, so I want to know how WaveSecure achieve its locking function, as the following picture show: http://goo.gl/XlPP When the mobile is locked, WaveSecure can require customer to input their own password. So I think WaveSecure must replace Android's original locking function. And I also google it, but I didn't find anything helpful. I only find two packages may be helpful. They are: android.app.KeyguardManager android.os.PowerManager But after I reading the Android Docs, I still can't have an idea on it. Can you help me? Thx:)