I'm sure Tesla is working hard to try and prevent that; few electronics manufacturers like people messing with their code. Different interests though; with Apple and co it's to prevent free / pirated apps (and them missing out on app store income), and maybe to a lesser degree prevent their platform from looking bad by bad apps. With Tesla it'd be more of a liability issue, I'm sure.
http://www.teslamotorsclub.com/showthread.php/58951-Let-the-...
(That starts out with parts, but the guy eventually roots his own car.)