Activation Lock is a security feature introduced in iOS 7. When a user enables "Find My iPhone/iPad," the device automatically locks to the Apple ID. This means that even after a factory reset, the device cannot be activated or used without the original Apple ID and password. While this feature was designed to deter theft, it has also created a significant problem in the secondhand market: many sellers forget (or refuse) to properly sign out of their Apple ID before selling, leaving buyers with an unusable device.
With Activation Lock ON, no one — not even after a factory reset — can use the device without the original Apple ID. While this protects against theft, many used iPhone sellers forget to sign out of their Apple ID — leaving buyers with a "brick" device that cannot be activated or used. Removing an activation lock without the original Apple ID requires Apple's official intervention, which takes 1–2 weeks and requires the original purchase receipt.
Before purchasing any used iPhone, iPad, Mac, or Apple Watch, always verify that the Activation Lock is OFF. An IMEI check with IMEICheck provides this information instantly — just enter the device's serial number and get results in 3 seconds. This simple check can save you hundreds of dollars and weeks of frustration.
