Android phones, apps and tablets

Instamapper

www.instamapper.com

Free app that provides real time GPS tracking - sort of like Google Latitude but more accurate.
You register your device with you account and when running in the background on your android (or iphone) it will send a GPS co-ordinate every x seconds (which is adjustable)
It does cane your battery if you don't use it wisely, but you can also send SMS's to it to remote fire the app and provide a location.
Have been playing with it for a couple of days and it's not bad for something that's completely free

This is pretty cool, how do you do the SMS remote opening?