Quote from http://www.gottabemobile.com/2016/02/25/...
Apple’s iOS 9.2.1 update is focused on fixing problems but it also brings some problems of its own. Today we want to take a look at these iOS 9.2.1 problems and provide you with some resources that should help if you run into an issue with Apple’s current upgrade for iPhone, iPad and iPod touch.
In December, Apple confirmed an iOS 9.2.1 beta for iPhone, iPad and iPod touch. The beta confirmed the existence of an iOS 9.2.1 update but it didn’t confirm a release date.
In mid-January, without warning, Apple took the iOS 9.2.1 update out of beta and released it for iOS 9 users around the world. iOS 9.2.1 is a small incremental update but it could have a big impact on iPhones, iPads and iPod touches.
iOS 9.2.1 is a bug fix update that also delivers security fixes to the iPhone, iPad and iPod touch. It also, according to some iOS 9.2.1 users, brings some problems of its own.
iOS-9.2.1-4
This isn’t surprising to us and it shouldn’t be surprising to you either. iOS updates, even tiny ones like the iOS 9.2.1 update, always bring problems with them. Apple’s beta wipes out the most glaring issues but problems always slip through the cracks.
The iOS 9.2.1 update is now a month old and we continue to see complaints about iOS 9.2.1. We expect complaints about the iOS 9.2.1 update for weeks, even after Apple releases its next iOS 9 update. (Probably iOS 9.3.)
With that in mind, we want to outline what you need to know about these issues. This roundup provides a quick look at current iOS 9.2.1 problems, fixes for iOS 9.2.1 problems, and more.
iOS 9.2.1 Problems
Apple fixed those pesky iOS 9.2.1 Safari issues but there are still a number of problems with the latest upgrade.
iPad Pro users are complaining about keyboard lag issues that apparently persist after the iOS 9.2.1 update. iPad users are also complaining about a volume indicator bug that carries over from the previous version of iOS 9.
iPhone users are complaining about perceived bad iOS 9.2.1 battery life.
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Just Released by iFixit
Confirmed: Apple’s Error 53 Fix Works
This morning, Apple apologized to its customers and admitted that Error 53 was a mistake—as opposed to a deliberate security feature. They also released a patch to iOS 9.2.1 that purports to fix Error 53—un-bricking phones disabled by the problem and preventing it from happening in the future to phones repaired outside of Apple's network.
Of course, we had to test the repair procedure ourselves. We’re pleased to report that the fix successfully fixed our Error 53ed iPhone 6s, and the process is refreshingly straightforward.
Visit our blog for more on our analysis.
http://ifixit.org/blog/7924/error-53-fix...
Nice job, Apple! Rolling out a fix is not only a win for consumers—but a clear victory for the right to repair your stuff. But there’s still a lot of work left to do to ensure that owners and independent repair shops have all the parts, tools, information, and support they need to fix products. And we’re going to continue to fight these battles publicly, in front of the Copyright Office, in front of lawmakers, and wherever else they need to be fought.
You can head over to Repair.org to check out all the other ways we’re working to make sure people can fix stuff when it break.
kaykay@ifixit.com.
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