structure

game menu buttons
    single player
    multi player
    score
    help

multiplayer menu
    "select mode:"
    mode buttons
    "pick connections:"
    list of connections

    enable bluetooth if necessary
    set up server, client, in other thread

    client picks device and mode, try to connect with server
    server gets dialog specifying mode and opponent: accepts and start game, or reject and continue listening
    if accept, each get own socket for communication, close other sockets

game mode
    time
    next piece
    score?
    animation change?
    message on game over

multiplayer messages
    thread for listening
    send message when clearing row
    decide on random or controllable effect (random is easier)
    game over message