Firstly, please make sure you are running the latest iOS version of Heroes Of Twilight. To do so:
  • Enter your device Settings > General > Software
  • There, you will see if there any available updates for the app.

If this does not fix your crashing problems, check your device's storage capacity:
  • Enter your device Settings > About
  • Check the available capacity. Do you need to free up space? We recommend removing unused videos, pictures and apps.
  • We also recommend you free up memory on your device by double-tapping the Home button and and close all other running apps.

Restarting your device may also fix the problem:
  • Hold down the "Sleep" button for a few seconds until you can slide the "OFF" button to shut down the device.
  • After waiting for a few seconds, hold down the "ON" button to turn the device back on.

If none of the above has worked, it's possible that the application's data has become corrupted. Delete the game from your device and then re-download it.

For more information about iOS troubleshooting, please refer to http://www.apple.com/support/.