Ipad air after update keep crashing any app

Try restoring to Factory Settings. This will reload a fresh copy of the iOS software onto your device:

Restore to Factory: Connect your device to iTunes on your computer, backup, and then select Restore to Factory.

See here for more information on Restore to Factory: https://support.apple.com/en-us/HT201252

If this doesn’t work your device may have developed a hardware problem. Contact Apple Support: http://www.apple.com/contact/

These are standard troubleshooting steps that you can try. Try them in the order in which they are listed here.

Go to Settings>Safari>Clear History and Website Data

Close all apps. Press the Home button two times quickly. You'll see small previews of your recently used apps. Swipe left to find the app you want to close. Swipe up on the app's preview to close it.

Next, force restart your device. To force restart your device, press and hold both the l/Wake and Home buttons for at least ten seconds, until you see the Apple logo.

If those three things made no difference, try this. Reset all settings. You will not lose any data, but all of the device settings will have to be entered in the settings app again including WiFi network passwords. The device will also reboot on its own. Settings>General>Reset>Reset all Settings.

If all of that fails, restore the iOS software. Backup your iPad before you restore, then restore the backup when you are done. If that still doesn't help, restore your iPad as new and start all over again. Most purchased content can be downloaded again at no charge as long as you use the same Apple ID and as long as the content is still available in the store.

Restore iPad to Factory Settings

Use iTunes on your Mac or PC to restore your iPhone, iPad, or iPod to factory settings - Apple Support

Then you had best contact Apple Support: http://www.apple.com/contact