Hyperlinks in Mail for iOS 9.3.1 still unresponsive and freezes the app.

Try Recovery Mode

https://support.apple.com/HT201263

I got the notice from Apple that problem was fixed w release 9.3.1 .

I Installed it while crossing my fingers! Well, let me tell u! Not really! It is NOT FULLY REPAIRED. It did improve but still freezes!

Since I've my temp solution (another thread) which WORKS, I'll delay using Mail & Safari full blast until it's fully repaired.

In my humle opinion there are some apps on your devices that caused of freezing.

Apple takes care about iOS not about all of 3rd party apps in the App Store I think.

Try to clear chache in Safari

1. Launch the Settings app from the Home screen of your iPhone or iPad.
2. Scroll down and tap on Safari.
3. Now scroll all the way to the bottom and tap on Advanced.
4. Tap on Website Data. Notice here you can see how much space on your iPhone or iPad website data is taking up.
5. Scroll to the bottom again and tap on Remove All Website Data.
6. Confirm one more time you'd like to delete all data.