In this paper we describe a system that allows users to annotate digital photos at the time of capture. The system uses camera phones with a lightweight client application and a server to store the images and metadata and assists the user in annotation on the camera phone by providing guesses about the content of the photos. By conducting user interface testing, surveys, and focus groups we were able to evaluate the usability of this system and motivations that will inform our development of future mobile media annotation applications. In this paper we present usability issues encountered in using a camera phone as an image annotation device immediately after image capture and users' responses to use of such a system. Categories & Subject Descriptors: H.5.1 [Information interfaces and presentation (e.g., HCI)]: Multimedia; H.4.3 [Information systems applications]: Communications Applications; H.3.m [Information storage and retrieval]: Information Search and Retrieval General ...