I get an 'Unauthorized User' message when entering the game
The game checks its download status with Google.
If you’re seeing this message, make sure your current Google account, activated on your device,
is the one you used when purchasing the game.

If I want to install the game on my new device, will I have to pay for it again?
You can install the game for free on your new device, from the Android Market.
Just make sure you’re using the same Google account as the one you used for your first purchase.

How do I play a multiplayer game?
Multiplayer works by connecting two devices on the same local area network, through WiFi.
Online multiplayer is not supported right now.
You'll be able to connect your device to an iPhone, iPod touch, iPad or Android device.

For Local (WiFi) matches, one of the devices should host the game and select 'Create Server'.
The other device should select 'Join Server'. The server should automatically appear on the hosts list, once it's created.
If it doesn't show up, you could press 'Manual Connect', and enter the server IP.
You can find the IP on the server device, inside the level select screen.

Once you're connected, the server selects the level, and you can start playing.