In order to make sure you can recover your progress in the event of having to reinstall the game or switch devices, you should make sure to connect to a Google Play account.

You can connect by simply going to the in-game settings menu and pressing on the "Connect" button next to the "Google Play" option at the top of the window. At this point, you'll just have to choose a Google Play account to log in with in order to finish connecting.

At any time after this you can recover your progress if you lose it by simply reconnecting to Google Play once again in the settings menu.