If you experience game crashes/freezes, we recommend that you complete the following steps in order to avoid them:
1) Clear the game cache:

a. Press your device's Home button.
b. Press your device's Menu button.
c. Tap Settings (or System Settings).
d. Tap Application Manager (or Apps).
e. Scroll to find the game app, then tap the app icon.
f. Tap Force Stop.
g. Tap Clear Cache.
h. Reboot your device.

2) Make sure your operating system is up to date.
3) Free up some memory on your phone.
4) Make sure your device is not in the energy-economy mode.