Though cameraphones are rapidly becoming the dominant platform for consumer digital photography, users still face difficulties in transferring, managing, and sharing photos captured with cameraphones. The Mobile Media Metadata 2 (MMM2) system removes the difficulty in transferring photos from the device by providing an automatic upload capability and uses metadata about the context in which a photo was captured to simplify photo management and streamline the sharing process. In our MMM2 system, we have leveraged collaborative filtering techniques to infer the likely sharing recipients for photos based on contextual metadata, which allows the system to accurately guess likely share recipients for a photo and present them to the photographer at the time of capture. Categories and Subject Descriptors