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The iOS, which runs the show, is designed so that if an app crashes, it does it without affecting other processes. A crashed app typically just disappears, at which point you’ll find yourself back at the Home screen. Tap the app to launch it again and you should be fine.
If the problem persists, check for an update at the App Store. Also read the release notes for the app; developers must submit their apps to Apple for approval, and if a bug has crept in, there’s a lag between when an updated version is submitted and when it becomes available.
If that doesn’t work, delete the app from the iPad and reinstall it.