Large displays are helpful tools for knowledge discovery applications. The increased screen real estate allows for more data to be shown at once. In some cases using virtual reality visualizations helps in creating more useful visualizations. In such settings, traditional input devices are not well-suited. They also do not scale well to multiple users, effectively limiting collaborative knowledge discovery scenarios. Smart phones and tablet computers are becoming increasingly ubiquitous and powerful, even having multi-core CPUs and dedicated Graphic Processing Units (GPUs). Given their built-in sensors they can serve as replacements for currently-used input devices, and provide novel functionality not achieved with traditional devices. Furthermore, their ubiquity ensures that they scale well to multi-user environments, where users can use their own devices. We present an application-independent way to integrate smart phones and tablets into knowledge discovery applications as input devices with additional functionality. This approach is based on Marking Menus, but extends the basic idea by employing the special capabilities of current consumer-level smart phones and tablets.