Q: IOS 9.3 battery drains

disable app background refresh and enable battery power mode

Hi! First of all, you're not talking to Apple right now, it's a user to use forum.

Follow the steps below.

Try to reset your device. This won't delete your data stored on this device.

• Press and hold the Sleep/Wake button
• Press and hold on the Home button
• Keep holding both buttons until the display turns off and back on with Apple logo on it.

Alternatively, you may go to Settings - General - Reset - Reset All Settings

If this does not help, restore your device to factory settings. Note that this will erase the data from your device.

Take a look this Apple Support article: Use iTunes to restore your iPhone, iPad, or iPod to factory settings - Apple Support.

Here you can find some useful tips on how to make the battery life of your device longer. They work for both iOS 8 and iOS 9.

http://www.imore.com/battery-life-problems-ios-9-heres-fix

https://www.apple.com/batteries/maximizing-performance/ 

http://www.idigitaltimes.com/ios-82-battery-life-problems-how-fix-quick-drain-is sues-iphone-ipad-and-ipod-422229

If these steps don't work, contact Apple and ask for help. This may be a hardware issue.

https://www.apple.com/support/iphone/contact/ 

Hi. Try some steps here: Battery Saving Tips for Your Beloved iPhone

How old is your device? If all aforementioned steps don't give battery life improvement it is high time to take your device to the Apple Store.

Send your feedback to Apple. So far i did not encounter battery life issue.

http://www.apple.com/feedback/

You are welcome. Hopefully they will find the best solution. anyway consider all previously suggested options one more time.

IOS 9.3 is very slow loading apps while on wifi... 9.3 is not good!!!!!

I have the same issue.. a perfectly working 6 Plus before the update.. a battery eating P.O.S. after 9.3.. it ate a fully charged battery in 2 hours sitting on my desk... the case temp was over 45c.... I downgraded back to 9.2.1 and the world is good again... fix  the update......

iPhone 6 iOS 9.3 MY battery stinks after upgradlong after 1hr of regular use it drained to 60%.

and 2nr use draines to 25%

WHAT EVER YOU DO DO NOT UPDATE

MY IPAD PRO IS ALSO VERY SLUGGISH!

and On both de the battery life is terrible!

My keyboard on my phone is glitchy and randomly tyPing exclamation marks.

fix this update make 9.3.1 and speed my devices up and fix the battery life!