The II2CPP error is unique to the Unity engine. It is called when the device doesn't have enough free Cache space for Unity to run correctly, so instead of starting the App it shows this error and stops running the application.
Fixing the problem
We suggest trying the following first before you try anything else:
- Clean Cache on All/As many Apps that you are able to
- Delete all cached History in Chat Apps
- Free up your mobile devices Internal memory (Not SD Card for Android users)
For most players these suggestions help them get back into the game.
If this doesn't help then we suggest visiting the Unity forums about this issue here.
We also have some other suggestions that may help, and have listed them in order from Most Recommended to Least Recommended:
- Clear the Cache of as many Applications that are installed on your device then try playing Gems Of War (Further explained above).
- Wipe your mobile device Cache Partition - follow the steps on this video (though you may need to find a step by step solution more specific to your device)
- Try playing on another mobile device.