Apple TV: Go to Settings > Apps and turn on Automatically Update Apps. If you don't have automatic updates turned on, you can open the App Store, go to the Purchased tab, and open an app's product page to see if an update is available.
Reinstall the app
iPhone, iPad, iPod touch: Open the Settings app. Tap General, then tap iPhone Storage (or iPad Storage). Tap the affected app, then tap Offload app. Tap Offload app again. Wait a moment for the app to offload, then tap Reinstall App.
Apple TV: Highlight the app on the Home screen, then press and hold the Touch surface until the app jiggles. Press Play/Pause, then select Delete. Open the App Store and redownload the app. Some apps require subscriptions for activation. If you can't activate the app or you don’t remember your sign-in information, contact the app developer.
Apple Watch: Open the Watch app on your iPhone and tap the My Watch tab. Scroll to the app you want to remove, then tap it. Turn off Show App on Apple Watch, and wait for it to disappear from your watch's Home screen. To reinstall the app, scroll down to Available Apps in the My Watch tab and tap Install.
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