PSA: Some Of Your Apps Might Not Work w/ iOS 11
If you've owned your iPhone 6 or iPhone 6 Plus for awhile, and many of you have, you probably have a pretty large collection of applications. And while most of your apps will probably work with iOS 11 there's a chance some won't.
iOS 11 brings an end to iOS support for 32-bit applications. Apps that haven’t been updated to support 64-bit will no longer work on your device.
Tons of apps haven't been updated to support iOS 11 and the list includes several popular games including Flappy Bird (if you still have it).
Unfortunately, there's nothing you can do to get them to work. They require an update from the developer and in many cases, the developer's no longer supporting the app.
If you want to look at what apps no longer work with iOS 11 you’ll want to open your Settings app. From there, tap on General, About, and then tap Applications.
If you haven't upgraded to iOS 11 yet, keep this in mind.