My battery is draining faster after iOS 14.4 update

Protect & Prolong life of your iPhone's Battery:

1. About the battery usage on your iPhone, iPad, and iPod touch ...
2. Batteries - Maximising Performance - Apple (IN)
3. iPhone Battery and Performance

Try some of these options too.

1. Avoid Screen Mirroring
2. Put on Low Power Mode
3. Put Auto Lock On (1 min):- with low power mode it will be 30 Sec
4. Put Auto Answer Off
5. Disable Push notifications for apps you do not use often
6. Keep your iPhone Face down to prevent notifications to light up screen
7. Enable Auto Brightness:- Settings > General > Accessibility > Display Accommodations > Auto-Brightness [Enable]
8. Manually lower brightness from Control Center
9. If you Want to watch continuous Video. Stream it on TV or a Monitor
10. 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
11. Location services to be allowed only while using the app
12. Set your iPhone to fetch email and calendar data from internet less frequently
13. Turning off Background App Refresh 
14. Charge before it drops below 20-30%
15. Try connecting to trusted Wifi where ever available in stead of Cellular
16. 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
17. Switch off Wifi & Bluetooth while in Roaming or Not in Range
18. Enable "Wifi Assist" : Settings > Cellular or Settings > Mobile Data > Wi-Fi Assist [Enable]
19. Periodically Check your Battery Health (Settings > Battery > Battery Health)

Yes, I have this problem too.

I waited months before upgrading to 14.x (from 14.6.1) and after experiencing 14.4 I clearly should have held off longer.

Just sitting at the home screen with no apps running... on 14.4 my phone gets warm and 1-yr old battery (reported at 90% health) goes down in charge 3-4% every minute.

After struggling for a day to find way via Settings to resolve the battery/heat problems --- I went to restore to 13.6.1 via iTunes and find that Apple has blocked that option by no longer providing signed versions of iOS 13 to iTunes. Appalling and heartless of Apple to do that when apparently version 14 is crippling MANY MANY devices.

So many in fact that getsupport.apple.com appears to currently be overloaded. :(

The 'Answer' by SravanKrA has good general tips but even all together cannot address the real power consumption problem in iOS 14(.4?). Its something that needs to be addressed ASAP by Apple.

In the meantime, WE NEED APPLE TO RESIGN the last few iOS 13.x versions to allow backups with those versions to be restorable to our devices via iTunes!!

what a ridiculous and unhelpfull comment.

I shouldn't have to recharge my iPhone after only 15 minutes of use on iOS 14.4 when I could use it for 4-6 hrs of continuous use two days earlier on iOS 13.6.1.

Apple is not in control of when and how long you charge the device. You are not charging it when you can.

Good luck.