That happened to me for a short period of time after I updated. It didn't do it with all apps, but it did it with a few here and there. Try a few basic standard troubleshooting steps. Close all apps and reset the iPad.
In order to close apps, you have to drag the app up from the multitasking display. Double tap the home button and you will see apps lined up going left to right across the screen. Swipe to get to the app that you want to close and then swipe "up" on the app preview thumbnail to close it.
Reset the iPad by holding down on the sleep and home buttons at the same time for about 10-15 seconds until the Apple Logo appears - ignore the red slider if it appears on the screen - let go of the buttons. Let the iPad start up.
You can also try resetting all settings. You will not lose any data, but most of the device settings will have to be entered in the settings app again. Settings>General>Reset>Reset all Settings.
Hopefully it will be something simple, but don't rule out restoring the iOS software, if nothing else works, but start with this easy stuff first.