There are hundreds of puzzle games available to buy on the handheld console; however some of the best include 'Slitherlink', 'Meteos', 'Picross' and 'Zoo Keeper' (pictured). The basic idea of the latter is to line up three or more animal icons on the eight by eight grids to make them disappear and produce more animals. It provides hours of entertainment, lots of fun and has highly addictive game play.