The current generation of Palm PDA devices is designed to share information records primarily with a base desktop system, or a server. Therefore, their built- in features for sharing data during ad-hoc collaboration among groups of mobile users are inadequate. In this thesis, we describe a new framework that addresses this problem by allowing users to transparently share the record databases of common applications during spontaneous collaborative sessions. The framework also allows users to define custom sharing policies for each application/user pair. These policies determine the manner in which records are exchanged and update, thereby automating the process of handling conflicts and preserving user privacy preferences. We also present implementation results, in which we have used the framework to create shared versions of common applications, such as Calendar and Memo. Our experimental results show that the programming effort involved is minimal and the user interaction with the application is, essentially, the same as in the original application.