Hand-held devices possess a large potential as an interaction device for their today's ubiquity, and present us with an opportunity to devise new and unique ways of interaction as a smart device with multi-modal sensing and display capabilities. This paper introduces user interaction techniques (for selection, translation, scaling and rotation of objects) using a camera-equipped hand-held device such as a mobile phone or a PDA for large shared environments. We propose three intuitive interaction techniques for 2D and 3D objects in such an environment. The first approach uses the motion flow information to estimate the relative motion of the hand-held device and interact with the large display. The marker-object and marker-cursor approaches both use software markers on the interaction object or on the cursor for the various interactive tasks. The proposed interaction techniques can be further combined with many auxiliary functions and wireless services (of the hand-held devices) for seamless information sharing and exchange among multiple users. A formal usability analysis is currently on-going.