Sometimes Google Play store updates cause problems with Android applications - the app download process gets stuck (e.g. showing 97%) and never finishes. Occasionally errors 907 or 963 may also pop up because of this.
To fix these, check the solutions below:
- You may need to clear cache and data of the Google Play Store app on your device:
Go to: Settings → Apps → Select Google Play store app → Select Clear Cache
If that doesn't help, try selecting Clear Data.
- It is also possible to uninstall the Google Play update and roll back the app version to fix the issue:
Go to: Settings → Apps → Select Google Play store app → Select More at the top of the screen → Select Uninstall updates.
- After that go to the Google Play store and download the GuitarTuna again.
Please also check Google Play Support for more information: Play Store won't load or download apps