Did you see the multidevice game demo during the Google I/O keynote? If you missed it, running Chrome on several devices, Google was able to show a game taking advantage of every screen on the desk. By drawing a race track across all of the devices, various colored cars were able to race around the track, from screen to screen, device to device.
Thankfully, Google isn't keeping the game, called Racer, to itself. You can use Chrome on your Android or iOS device to play the game with friends and family members right now.
Once there, you'll need one user to start a race and the other users to join a race. The user who started the race will have a short code for everyone else to enter and connect to the same race. The best part is, you don't even have to be connected to the same Wi-Fi network or a Wi-Fi network at all; Racer works across multiple devices over a cellular connection.
Once everyone is connected and has picked a color, the race creator can select a difficulty level, and then you'll need to line up the devices using the onscreen instructions. After that, the race is on. Touch the screen to go, release to slow down or stop.