Rules of the game Gem Blokus:- A board with 20 * 20 squares.- 4 players having each 21 pieces : 1 single-square, 1 domino, 2 triominos, 5 tetraminos and 12 pentaminos.- As player, I shall place on the board most of my pieces.- For first round, I must place a piece so that it touches one of the corners of the board.- Next, a piece must be placed so that it touches a corner of one of my own pieces. It may touch several corners, but never any edge of my pieces!- If I cannot place any more piece I pass my turn.- The end of the game is reached when every player passes.- My score is : addition of all the squares of the pieces I placed.The app does collect user data, all the data is saved only on the mobile device.