You are a Sunday computer scientist (or any other day) and you are not "very bad" in programming, you want to taste the development of applications for Smartphone under Android without aiming to dethrone Google or Microsoft and others ( or at least you won't say that I tipped you off), then this little book is for you.It is prepared by a fairly experienced computer scientist, but not specialized in the field, and above all very lazy and unwilling to "digest" all the documentation necessary to fully understand the subject. It is an intuitive approach that will be adopted: a progression by trial and error "without map and without compass". A short hike in the country of Android which I hope will be pleasant, without worrying too much about the versions (hardware and software) which evolve too quickly, nor about questions related to the distribution of applications, in particular through "stores" and especially without claiming to make it an exhaustive tutorial.Programming for discovery and fun is the main focus of this book.