1. Open "Settings-General-Background Program Refresh" and select to turn off refresh. PS: Actually, turning off refresh will not affect message reception;

2. Open "Settings-General-Auxiliary Functions-Reduce Animation Effect" and select "On" to reduce animation effect and save memory;

3. Open "Settings-General-Accessibility-Enhance Contrast-Reduce Transparency" and select "On". After opening, the drop-down screen has no translucent glass effect, but it will be much smoother;

4 Open "Settings-Privacy-Diagnosis and Dosage" and choose not to send;

5. Open "Settings-Privacy-Advertising" to restrict advertising tracking;

6. Open "Settings-Privacy-Location Service" and select always, in use or never for the corresponding APP according to the actual situation;

7. Most of "Settings-Privacy-Location Services-System Services" can be turned off, and my personal test will not affect the use;

8. Turn on "Settings-Privacy-Location Services-System Services-Frequently Visited Places" and it is better to turn it off, otherwise it will waste resources and traffic to continuously record geographic information;