My iPhone 4 won't turn on or do anything after using the Find My iPhone app to find it. I already tried to fully charge the iPhone and pushing the power button, but nothing works.
Ask Different is a question and answer site for power users of Apple hardware and software. It only takes a minute to sign up.Sign up to join this community
Press and hold the Sleep/Wake button and the Home button together for at least ten seconds, until the Apple logo appears.
Normally when you've locked your iPhone by using the app, you have entered a 4 digit password and you just have to enter the code to start using the iPhone again.
If you have forgotten your code, you can try to connect it to iTunes and restore it over there. But you'll lose all your data of course.