I`m trying to make an example of cooperative mini-game. Something like that: five people at the same time on different notebooks or tablets or smartphones should press and hold the big-red-button for a second. When the last one will press and hold it for a second, everyone of them will hear... ummm... TADAAA.
For some reason i`m sure that somebody already posted something relevant here but i had no luck to find it. Can anybody help me?