I have multiple locate apps. The only issue I have is the whole if you turn off data it won't work. Cerberus and where's my droid depends on data being on and since I'm on a galaxy nexus with 2x battery app (turns off data connection). Then you're at the mercy of a person actually having and using your phone.
My most recent case, the phone slipped out of my pocket and in silent mode. the car owner wasn't around to hear the phone (I remotely downloaded remote ringer).
The same thing if you're low on battery, have a lock screen.
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