Here's a battleship-type game that can be used for a whole-class speaking activity with middle school students. Students raise their hand and ask 'yes' or 'no' questions according to information provided on the grid to try to find and sink the ships. Teacher should just tap each square to reveal a hit or a miss, the 'yes' or 'no' part doesn't really matter. There are sound/graphic effects so the kids get into it. It may take a minute to get them to understand exactly how to play, but after a bit they should get the hang of it. The grid can be changed to suit your vocab review or question format practice needs.
Hope this helps someone!