I ordered this under the mistaken impression that it would help with coding games for various touchscreen platforms, which unfortunately wasn't the case. However, the book is useful in a number of different ways and is a great way to get thinking about the practicalities of designing a game. It will help you bypass, or counter, areas of difficulty you may come across along the way and will help you to flesh out your basic concept. Things like the controls, themes, interfaces and so on are covered here and it can help a wannabee designer be able to get from the inital idea to a full round concept and plan for a game.
The book is well written, obviously by someone who knows what they are doing, and features interviews with some successful game designers, so you can hear real life case stories. It is all written in a light hearted, easy to read way and will be of use for anyone who his serious about creating a touchscreen game, helping guide you along the way.