It's called MyLink, and only available through OnStar for 2011 Models(excluding malibu)
You must also have an active subscription to OnStar.
will NOT work with earlier years, also some issues with it working on the 2011 regal.
(2011 onstar systems are Gen 9 equipment)
It requires an iPhone or Android(2.1 or better) operating system
I have the App but it will not work on my phone(i have android 1.6) since AT&T haven't updated to 2.1 but the updates are currently being released every few weeks.
For most vehicles, you can lock/unlock, view fuel levels, oil life remaining, and tire pressures.
For the ability to start the vehicle by MyLink, you need to have the factory installed remote start option.
The Volt has other options through the app in regards to charging and battery levels etc.
However, there are alarm/automation systems out there that works through your phone...
Here is Vipers version...
http://www.androidtapp.com/viper-sma...ock-plus-more/