There's an Android Application called Smart Taskbar that manages to Pin a small SemiTransparent Icon over the screen...The icon remains visible over ALL the activites (including the home screen). The Icon is Clickable (/Touchable), and it does popopen a Small Popup window which the user can interact with.
I'm very interested in how this is done? I think it's something to with PopupWindow.
Any ideas? Thanks in Advance.
I recently experimented with this.
See this question: Creating a system overlay window (always on top) - the solution is virtually the same, but you need to set TYPE_SYSTEM_ALERT in the layout params instead of TYPE_SYSTEM_OVERLAY.