For Android
- Open “Settings”.
- Tap “Apps”.
- Tap the unresponsive app.
- Tap “Force Stop”.
- Tap “Force Stop” to confirm.
- Relaunch the app.
For iPhone, iPad, and iPod touch
- Double-click the Home button to show your most recently used apps.
- Swipe right or left to find the app that you want to close.
- Swipe up on the app’s preview to close the app.
- Relaunch the app.