This app[0] made the rounds last year and caused a bit of a stir: it keeps your android phone's battery at a constant state, prevents the screen from turning off, and flips the screen orientation, all of which from a disconnected interpretation of halacha should be permissible. Problem is, any touch to the screen completes a circuit (one of the prohibited categories of work) so the whole thing is a bit ridiculous anyway.

[0] http://shabbosapp.com/how-it-works/ https://www.youtube.com/watch?v=aEDHi09oyXY http://en.wikipedia.org/wiki/Shabbos_App