For Android devices:
We recently added a backup/sync system that is linked through your email address. You have to activate it on one device at a time. For example, on Device A (the device with your current game), go into the Pocket Trains Options menu and enable Cloud Services. You will need to enter a valid email address where we can send you an email. Once you get the email go back to the the Options screen on Device A, and enter your activation code to complete the registration. You can confirm it is registered by tapping the Cloud Services button again and it will show your email address and registration status.
You can then go to Device B (The device you want to sync your game to) and repeat the above steps, including getting a new activation email with code to be entered on the new device.