Thumb + Pen Interaction on Tablets

ABSTRACT Modern tablets support simultaneous pen and touch input, but it remains unclear how to best leverage this capability for bimanual input when the nonpreferred hand holds the tablet. We explore Thumb + Pen interactions that support simultaneous pen and touch interaction, with both hands, in such situations. Our approach engages the thumb of the device-holding hand, such that the thumb interacts with the touch screen in an indirect manner, thereby complementing the direct input provided by the preferred hand. For instance, the thumb can determine how pen actions (articulated with the opposite hand) are interpreted. Alternatively, the pen can point at an object, while the thumb manipulates one or more of its parameters through indirect touch. Our techniques integrate concepts in a novel way that derive from marking menus, spring-loaded modes, indirect input, and multi-touch conventions. Our overall approach takes the form of a set of probes, each representing a meaningfully distinct class of application. They serve as an initial exploration of the design space at a level which will help determine the feasibility of supporting bimanual interaction in such contexts, and the viability of the Thumb + Pen techniques in so doing

Target selection on hand held tablets

The use of mobile devices has been increasing and besides mobile phones, other devices have strongly established themselves in the market, that is the case of tablets. Although tablets might seem similar to modern-day smart phones the truth is that both kind of devices have differences that make their users interact with them in different ways. For instance, the size of a tablet is larger than that of a smart phone and that leads to differences in the grasp, that for a tablet results better to hold it with both hands. As a result of this two-handed grip, it is only possible to operate the device with the thumbs. Although there is already some body of work that has studied the target selection times with tablets using this kind of grip, nothing has been researched so far about a distinction and influence of the angle of approach to such targets. We believe that the biomechanical configuration of the hand leads to differences in the selection times when moving the thumb since it can be observed that the thumb cannot move towards certain regions with the same ease than when it moves to other positions. We have planned and designed an experiment that evaluates the thumb selection times for different angles while on a tablet that is grasped with both hands in landscape mode. Our target was to determine if there are differences in the time to reach a target between different angles of approach. Finding these differences would help to define a proper model that describes such behavior and also understand for which conditions of angle and amplitude it is easier or more difficult for users to interact with these touch screen devices. We also analyzed if the direction of the trajectory followed by the thumb had an influence and could determine which areas and movements of the thumb correspond with fewer errors and fastest times during target acquisition