Ok for all that don't want to download the whole NC: LoquendoTTS Downunder's fan edition
But I know something you could include into your tool
A suicide.dat in the root of the device to make sure it turns off fully after the time (in sec.) set in it.
Works great for me and saves a lot of juice in my battery.
Of course you could add a wakeup.dat instead so that the user alsways has his device ready to go ROFL