https://www.youtube.com/watch?v=8_pHdeu4Rks

This is my submission for the Android Experiments 2016 contest.

Twenty-seven is a three-dimensional tic-tac-toe game where the grid is a 3x3x3 cube and a player can win by connecting three spaces in any direction, including diagonals. Each vertical plane is represented by a separate Android device.

The Android devices communicate via the Nearby Messages API.