iphone does not vibrate

Trick to fix iPhone phone not vibrate when there is an incoming message
the phenomenon that the iphone does not vibrate when there is an incoming message makes users feel inconvenient because they have to open the check. although it does not affect the quality of the device, many important and urgent messages will be ignored.
Fix broken iPhone error
recently, many iphone users update to ios version 9 public beta 2 encounter the situation that the phone does not vibrate when a call or message arrives. if you encounter this problem, you can refer to our fix below.