Section: New Results

Macro-dynamics

Participants : Stéphane Huot, Sylvain Malacria [correspondent] , Nicole Pong.

One conspicuous feature of the current evolution of interactive devices is the spread of touch-sensitive surfaces. Typically, modern smartphones are equipped with such touch-sensitive surfaces that also support normal force-based input capabilities, which can for instance be used to control the range of a text selection by varying the force applied to the touchscreen (on e. g., iOS devices). However, this interaction mechanism is difficult to discover and many users simply ignore it exists. To overcome this problem, we introduced ForceSelect (see Figure 6, left), a force-based text selection techniques that relies on a simple mode gauge (see Figure 6, right) that does not require additional screen real-estate and help users to discover and master the use of force input in text selection tasks [22]. We conducted two studies that suggest that this mode gauge successfully provides enhanced discoverability of the force-based input and combines support for novices and experts, whereas it was never worse than the standard iOS technique and was also preferred by participants.

Figure 6. (left) Example of text selection using ForceSelect. The user performs a long-press that displays the callout magnifier. Keeping the force in the character level, the user adjusts its position by moving her finger. She then holds the force in the word level of the “mode gauge”, locks the selection and enters the clutch mode. When force-pressing to the whole text level of the “mode gauge”, she un-clutches the selection and updates it.; (right) Close-up of the “mode gauge". There are two types of text highlighting in the background: dark highlighting covers between both handles and light highlighting acts as a feedforward of which portion of text will be selected if the user released her finger (here the whole paragraph).