The title says it all, this is a book about smartphones. That means handheld, touchscreen devices of any size up through "phablets." The focus will be on all-touch devices, but some attention will be paid to built-in keyboards and keypads, and pens as well. The focus for now is on Android and iOS, but I may add in Windows and Blackberry 10 as it proceeds. 

Why, you might ask, the narrowed scope? Well first because it helps keep the complexity down. I hope that you can pick this up and go to it when you have the specific need of designing Websites and apps for smartphones. But also because other devices are not so well-defined. Telematics (in-car displays) are really in their infancy, with the current interfaces mostly being terrible and inconsistent. Tablets even are the subject of mostly much poorer design, inheriting smartphone interfaces far more than they should. 

And most of all, I have found as I have performed the research and analysis that informs the concepts and patterns in this book, we simply don't have the knowledge of how people use these devices. Someday, I hope we will, and then maybe I'll be lucky enough to write a book on design for tablets.