Battery Drain by Microphone and Screenshots

Protect & Prolong life of your iPhone's Battery:

1. Put on Low Power Mode
2. Put Auto Lock On (1 min):- with low power mode it will be 30 Sec
3. Put Auto Answer Off
4. Disable Push notifications for apps you do not use often
5. Enable Auto Brightness:- Settings > General > Accessibility > Display Accommodations > Auto-Brightness [Enable]
6. Manually lower brightness from Control Center
7. If you Want to watch continuous Video. Stream it on TV or a Monitor
8. Don't force close apps; Apps which are not on frontend screen are paused by the system to save energy. Apps require more energy to re-launch. Apps which are open in the background use large memory is a myth and quitting them is counterproductive
9. Location services to be allowed only while using the app
10. Set your iPhone to fetch email and calendar data from internet less frequently
11. Turning off Background App Refresh 
12. Charge before it drops below 20-30%
13. Try connecting to trusted Wifi where ever available in stead of Cellular
14. Enable Airplane mode in areas with bad cellular and wifi coverage. Your phone keeps trying for reconnection with the missing / weak network. This uses lot of energy
15. Switch off Wifi & Bluetooth while in Roaming or Not in Range
16. Enable "Wifi Assist" : Settings > Cellular or Settings > Mobile Data > Wi-Fi Assist [Enable]
17. Periodically Check your Battery Health (Settings > Battery > Battery Health)

iPhone Battery and Performance

https://support.apple.com/en-in/HT208387

I’m on my fourth phone it’s doing the same thing it also changes my passwords and I get locked out of my screen I know the password right I keep reentering it finally it locks me out and I have to go to iTunes and reinstall my phone I’m so fed up with that I’m not getting help from Apple they just want me to buy a new phone

iPhones cannot be hacked or infected with Virus / malware / Spyware, unless you have downloaded spurious softwares or unauthorised apps directly from Internet