IPhone 16.2 upgrade

Please go through the following links.

• iPhone Battery and Performance - Apple Support (IN)

Protect & Prolong the life of your iPhone's Battery: Batteries - Maximising Performance - Apple (IN)

Try some of these options too.

1. Avoid Screen Mirroring
2. Put on Low Power Mode
3. Put Auto-Lock on (1 min):- with the Low power mode it will be 30 Sec
4. Disable Push notifications for apps you do not use often
5. Keep your iPhone Facedown to prevent notifications to light up the screen
6. Enable Auto-Brightness:- Settings > General > Accessibility > Display Accommodations > Auto-Brightness [Enable]
7. When possible, manually lower the brightness from Control Center
8. If you want to watch continuous Videos/Movies. Stream it on TV or a Monitor
9. Don't force close apps; Apps that are not on the frontend screen are paused by the system to save energy. Apps require more energy to re-launch. Apps that are open in the background use large memory is a myth and quitting them is counterproductive
10. Location services may please be allowed only while using the app. Avoid the "Always" option wherever available
11. Set your iPhone to fetch email & Calendar data from the internet less frequently
12. Turning off Background App Refresh 
13. Charge before it drops below 20-30%
14. Periodically Check the Battery Health (Settings > Battery > Battery Health)

Many users who have updated to iOS 16 and above must have a similar issue if the issues stated by you are due to the iOS.

Unless you state what the issue is many in this forum may not be able to respond positively to the issue you are facing. 

With the limited information that you have provided, It is hard to even guess the problems faced by you. 

You may get faster and better responses to your query by --> Writing an effective Apple Support Commun… - Apple ...

Please re-post with detail so that someone else can help.

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