My phone fell and the screen is cracked. When I turn on the phone, the phone vibrates to indicate that it's activated but...

If the phone does not turn on try these options: (1) Check if the battery is charged. If the battery is faulty and does not take in charge, the phone will not turn on. (2) If the battery does not turn on after charging then your battery may be faulty and you should replace the battery. (3) If the phone still does not turn on after changing and charging a new battery, then the motherboard may be faulty and should be replaced. For more help refer to: Motorola Photon 4G Troubleshooting Guide