This document discusses advertising on mobile devices and proposes some models for mobile advertising. It notes that mobile advertising is a growing market as mobile devices become more prevalent and capable. It argues that for mobile advertising to be effective, it requires permission from users and should provide some value in return. Some examples of mobile advertising models discussed include allowing free content, messages or airtime in exchange for viewing ads (like the Blyk model) and providing relevant sponsored information to users. The document also outlines various formats that can be used for mobile ads, such as idle screen ads, mobile applications, multimedia messages, video ads and location-based services. It emphasizes that an ideal mobile advertising model respecting users' permission and value exchange has not been