I am in pretty much the situation of this question: I'm trying to teach my four-year-old son the rules of chess, but the concept of "checkmate" is too abstract for a small child, so I want to tell him that the goal is to capture the king instead.
The problem is that I'm using an iPad app rather than a physical board (for a number of reasons, including the fact that the app will show you each piece's legal moves, so we don't have to explain all of the moving rules before we start playing).
Does anyone know of a chess app that both (1) shows legal moves (which most of them do) and (2) allows king captures (the feature I can't find)?