What's with Apple 7p's constant crash?

This is caused by too many functions of mobile phone or hardware problems of mobile phone.

First, turn off the functions that the phone doesn't need to use.

Second, the mobile phone turns on the power saving mode, and the specific methods are as follows:

1. First click "Settings" on the phone desktop.

2. Then select the "Battery" option in the setting interface.

3. Finally, turn on the switch in the column "Low battery mode".

Third, bring your mobile phone and warranty card to the nearest Apple official customer service center for repair.