Customizing Android Lock Screen Functionality?

I will like to develop an App which modifies LockScreen of Android. I have read in some forums that it is not supported as yet in the SDK but there are some applications available

Solution 1:

It is possible to have views displayed above the lock screen and to make it dismiss the lock screen. It's a dirty solution, but the only one as long as there is no api to replace the lock screen.

Android activity over default lock screen

http://developer.android.com/reference/android/view/WindowManager.LayoutParams.html#FLAG_SHOW_WHEN_LOCKED