In these days of constant buzz about the semantic Web and its various supporting technologies, I find it difficult to find material on applying these “in the small,” especially with regard to our myriad of portable devices. The authors of this work, all connected with the Nokia Research Center in Helsinki, have tackled aspects of this by investigating the concept of personal content, and what it means for the ordinary user of today’s powerful mobile personal devices, such as phones and media players. What results is a text combining descriptions of the emerging uses of mobile personal computing devices with some of the metadata infrastructure needed to stitch together personal content. This blend is both colloquial and technical, and will appeal to those interested in some ideas and proposals for improving the experience of using these devices. Anyone looking for answers to specific questions, or guidance on application development, however, will be frustrated. This is not a book suitable for those who want instructions on how to better organize their iPhones, nor is it for entrepreneurs wanting a recipe to build a killer app for smartphones.

The key to understanding the book is its central focus on the notion of personal content instead of data, and of content management instead of file management. Device users have long faced a challenge when wading through images, audio, videos, and other data on mobile devices, and device capacities continue to increase at a dramatic rate. Also thrown into this mélange are emails, calendar entries, phoning records, short message service (SMS) messages, location data, gaming artifacts, and so on. In effect, the authors pose the question: How can ordinary smartphone users describe and discover the attributes and relationships in and among all their content in a way that increases enjoyment and pleasure? This question is made more concrete in the form of short use-case scenarios sprinkled throughout the text. While at first I found these scenarios intrusive, I soon appreciated the insights brought to the material by the five different personas and the fictional (albeit plausible) stories.

Many of the ideas are developed through a thinking tool called GEMS (short for Get, Enjoy, Maintain, Share). Each of these four steps encompasses a range of activities that can be applied to some bit of content, whether it is obtained by the user (a photo, a message, or a song file) or generated by the platform (harvesting of context such as location, person called, date, and so on). The description of the life cycle of mobile and personal content is used repeatedly throughout the book. It is especially helpful in some of the largest and most technical chapters (chapters 4 and 5, “Metadata Magic” and “Realizing a Metadata Framework”), as it links typical user tasks to the construction and use of software frameworks developed at Nokia. The notion of content management is equated with metadata management, and the authors did well to minimize the need for the jargon common in such discussions. The text is blessedly free of figures and tables full of Extensible Markup Language (XML); the authors must have been sorely tempted to include such material.

Other topics vary widely throughout the book: descriptions of the limitations of small devices; technical challenges when synchronizing distributed content across personal computers (PCs) and mobile devices; user interface concerns and best practices, in the context of small form factors; dedicated media devices versus “Swiss-Army knife” devices, versus toolbox devices; and the list goes on. I think a reasonable reader might throw up his hands at some point and decry the lack of focus. However, it serves well as a crash course for the swirl of topics to be mastered in this interdisciplinary field. The book is well referenced, and can serve as a jumping-off point for someone who wishes to get started in this fascinating area of research and development.