Touch Projector: Mobile Interaction Through Video


The article describes a device called the Touch Projector which “allows users to manipulate content on displays at a distance, including those that would otherwise be unreachable. It further allows users to manipulate devices that are incapable of touch interaction, such as a wall projection, or a laptop computer. Users aim the device with one hand and then manipulate objects by touching and dragging it in the live video using the other hand. Touch input is “projected” onto the remote display, as if it had occurred on it.”

How content is transferred using Touch Projector:
i. The user aims at the desired display. The content is seen in the live video on the mobile device.
ii. The user touches the desired object and starts moving the Touch Projector device. As long as the device is pointed at the original display, the object keeps moving. It disappears as soon as its display leaves the device’s viewing angle.
iii. When dragging an item off-screen, a thumbnail is shown.
iv. After reaching the destination display the object can be moved to its final location by moving the finger on the mobile device.
v. Releasing the finger ends the drag operation.


The main advantage of this device is the user need not be in direct contact with a screen. Furthermore, the device allows interaction between several different screens with the ability to move content between them.

The automatic zoom feature seemed to really make the device more productive. The device zoomed out when it detected it was no longer pointed at a display and zoomed in automatically when it was pointed towards a screen. The user study also showed that the presence of this feature made users faster and less prone to error.

The freeze feature eliminates the necessity to hold the device still or pointed at the screen, avoiding unnecessary fatigue. Live video can be restarted with the click of a button. It seemed to make users more accurate in their tasks.

The article was well written and provided a great amount of detail. There are also pictures that illustrate the working device. Also, I really liked the fact that the authors mentioned all the limitations of the device.


Minor hand movements with mobile devices can create instable images which can consequently cause troubles for the user.

The researchers claim that they plan to study the effects of computer-generated graphics on mobile devices as an alternative for the camera stream. This suggests that there may be better ways to implement an application such as this.

The device suffers from poor performance for targets with small apparent sizes.