If you are connected to one of the Save features available on all Android and iOS devices (Google Play Games, Game Center, or Facebook), your purchases are saved with your account online.
Your progress can then be restored by going to ‘Settings’ and connecting to the same account once again. In case an item disappears anyways, you can restore permanent real money purchases (Double Coins, Characters and Boards bought for real money) directly in the game:
- Go to 'Settings'
- Scroll to the bottom
- Tap the button 'Restore Purchases'
It is, unfortunately, not possible to restore permanent real money purchases across device platforms (i.e. from iOS to Android).