Find a lost or stolen smartphone
Another great iCloud feature is Find My iPhone, which tracks your iOS and OS X devices, so you can find them on a map, send an alert (in case your phone is hidden under a blanket, for example) or message, and lock or wipe them if necessary. Just be sure you set the device so a thief can't turn off this feature. Again, Android can't join in.
But there's a comparable service called Lookout that lets you find, lock, or wipe a missing Android device from any browser. The basic version is free. However, be warned that it's easy for a thief to disable it if he or she notices it's installed.