Apple recently registered a patent for merging several modalities including gaze vectors for novel interaction methods. The direction of gaze is to be used in combination with finger gestures (or other input devices) to modify the object that the user is currently looking at. Will be interesting to see what types of devices they are aiming for. May not be high precision eye tracking since stability and high accuracy is hard to obtain for a 100% population in all environments.
From the patent document:
"There are many possible applications that would benefit from the temporal fusion of gaze vectors with multi-touch movement data. For the purpose of example, one simple application will be discussed here: Consider a typical computer screen, which has several windows displayed. Assume that the user wishes to bring forward the window in the lower left corner, which is currently underneath two other windows. Without gaze vector fusion there are two means to do this, and both involve movement of the hand to another position. The first means is to move the mouse pointer over the window of interest and click the mouse button. The second means is to use a hot-key combination to cycle through the screen windows until the one of interest is brought forward. Voice input could also be used but it would be less efficient than the other means. With gaze vector fusion, the task is greatly simplified. For example, the user directs his gaze to the window of interest and then taps a specific chord on the multi-touch surface. The operation requires no translation of the hands and is very fast to perform."
"For another example, assume the user wishes to resize and reposition an iTunes window positioned in the upper left of a display screen. This can be accomplished using a multi-touch system by moving the mouse pointer into the iTunes window and executing a resize and reposition gesture. While this means is already an improvement over using just a mouse its efficiency can be further improved by the temporal fusion of gaze vector data. "