all apps shut down

Have you tried any of the troubleshooting steps outlined in the manual? There is a bookmark in Safari for the manual.

I am having the same problem. I've followed all the suggestions given and nothing is working 😟..HELP

You have tried all of these?..

These are basic steps you can try if apps suddenly quit on you or if the your IPad starts to behave erratically. Quite often these simple fixes will resolve your issue.

Quit the app by double tapping the home button to bring up the multitasking/recents tray at the bottom, hold down on any of the app icons in the tray until all the icons wiggle, then tap the minus sign in the corner to quit the offending app or apps. Try your app again.

Restart the iPad by holding down on the sleep button at the top of the iPad until the red slider appears, then slide to the right to power off the iPad. Turn the iPad on again by pressing the sleep button until the Apple logo appears. Once the iPad has fully rebooted, find your app, and tap the icon to relaunch.

Try a hard reset by pressing and holding down on the sleep button at the top of the iPad while holding down on the home button at the bottom, until the Apple logo appears and the iPad restarts. Launch the app again and see what happens.

You need to restart iPad Hold down the home button and the power button at the same time until you see the apple logo. This fixed mine.

yes, this worked for me. I had problem that apps were crashing after some time. After I restarted the Ipad, now the apps are working. thanks.

No promises but a system Reset cures many ills and takes but a minute to perform:
Hold down the on/off switch and the Home button simultaneously until you see the Apple logo. Ignore the "Slide to power off" text if it appears.

A Reset does NOT delete apps, photos, movies, music or any other data. A Reset does NOT delete any settings for email, network access, etc.

Also, you might wish to download the 4.2 User Guide. Pay special attention to page 170.
http://support.apple.com/manuals/#ipad