why is my phone slower and why dise the power run out quicker after i updated it

After a major upgrade, there is a lot of activity going on in the background (syncing, face and object recognition, Spotlight re-indexing, performing house cleaning tasks, etc). The first few days after an upgrade are not an indication of normal usage. Give it time to settle down.

You can also try a Restart, just in case your particular issues have a different cause.

Restart your iPhone, iPad, or iPod touch - Apple Support

My phone is doing the same thing. Has been several days. Have restarted it. Went through trouble shooting g with my carrier. How do I back out of this defective release. It has made my phone in usable.

I have three Iphone 5SE / Iphone 6 and had been trying to get all the suggestions I can find and still problems persist. Getting real agitated by getting the Simplified Chinese back /forth with English (as well as the symbols) via keyboard switch, it has been a week and getting really upset with Apple for NOT even tried to test the IOS 11 before launched (60,000 employees NOT using iphones ???????) #^$(@&$(@$!! finally 11.1.2 was here, updated problems still remain!

Might as well tell me good, trusty way for my phone to revert back to iOS10 - (privately, it failed as somehow the older backups in itunes overwritten or may be prior to backup I have deleted older ones to save some space, well this is not Apple's mistake but mine). I n the meantime, I suspend the idea of getting the X for my wife until I read it is stable - SICKED !

Hi

You don't say what iPhone you have But if it's 2/3 years Old it may need a new battery.

Go to apps store download Battery life it will test your battery condition.

Cheers

Brian 🇬-1F1E7;