We kindly suggest to do the following steps, as the game might have recently updated and your files might have been corrupted:

1. Force Close the app;

2. go to Settings, Apps and select Clear Data for your game (don't worry, you won't lose your game progress);

3. Uninstall the app;

4. Restart your phone;

5. As soon as your phone starts, direct your browser to Nutaku to download the Nutaku Android Client for automatic game updates, available at nutaku.net. This will ensure that you're always up to date;

6. If you're asked to log in, use your Nutaku.net credentials.