Natural forms of interaction have evolved for personal devices that we carry with us (mobiles) as well as for shared interactive displays around us (surfaces) but interaction across the two remains cumbersome in practice. We propose a novel cross-device interaction style for mobiles and surfaces that uses the mobile for tangible input on the surface in a stylus-like fashion. Building on the direct manipulation that we can perform on either device, it facilitates fluid and seamless interaction spanning across device boundaries. We provide a characterization of the combined interaction style in terms of input, output, and contextual attributes, and demonstrate its versatility by implementation of a range of novel interaction techniques for mobile devices on interactive surfaces.