Truly dreadful interface. You move a piece to a specific square and somehow the piece misses the mark. E.g., I always play e4 as white. Today it registered the move as e3. I eventually reach a clear winning position with plenty of time. Instead of resigning, my opponent plays it out to the bitter end & is "rewarded" for his mediocre & unsportsmanlike play when the interface fail treats a winning move as a losing one. I love chess, but this app's horrible interface ruins the game.