A lot or a little?
Parents need to know that GEO Play is a geography game in which players locate world capital cities for points. Kids don't need to know the names of the capitals to play, and in fact this game is a good way to introduce them to those names. What is helpful is a bit of knowledge about the locations of countries, split into five regions. Kids can either play solo in Practice Mode, or against other players (friends or an "auto-match") via Apple's Game Center.