Find My iPhone/Mac can both lock a device remotely or wipe it clean. Apple goes so far as to allow a Good Samaritan to dial a number you've sent through Find My iPhone even when all other calls on the iPhone are disabled.
Use third-party software: Several third-party packages keep a constant low-level account of where a device is located. Others wait for a remote network trigger, checking in at regular intervals, that a device is stolen before they activate tracking. Some of them let you file a police report, see what a thief is typing, or even use your camera to snap a photo or video of the thief. Options include Gadget Track for Mac OS X ($20) and the iPad, iPhone, and iPod ($4); Absolute Software's Lojack for Laptops ($40 for 1-year subscription); and Orbicule's Undercover for Mac ($49) and Undercover iPhone/iPad ($5).
In all cases, the software has to be installed before a device is stolen, and typically registered and activated. You also want to run a test to make sure it can be located while still in your clutches.
Always be prepared
Its always hard to deal with the loss of an electronic device that contains personal and business data. By taking measures to secure your systems before you hit the road, you can defeat thieves before they get started, while helping Good Samaritans bring your precious hardware back to you.
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