The document discusses the "developer's dilemma" of what mobile applications to build. It suggests considering building applications, open APIs, community, platforms, services, experiences, and business models. The author is a mobile apps expert who has worked with many companies. He advocates building applications that exploit context like location and social networks. Opportunities for 2009 include mobilized social apps, video apps, enterprise social software, and cloud computing. Mobile drivers going forward include improved devices, greater dependency on web 2.0, more data-friendly pricing, app stores, and increased user participation.