Technical Glossary

The Essentials

TouchFree Application

TouchFree Application runs invisibly on top of existing user interfaces. Perfect for retrofitting systems with no need to modify your existing application’s user interface or change a single line of code. It provides a cursor that users control touchlessly and communicates with Windows’ input system to control your application.

TouchFree Application can also be used to evaluate the capabilities of TouchFree in advance of integrating TouchFree Tooling into your own Web or Unity applications.

TouchFree Tooling

TouchFree Tooling enables Web and Unity developers to integrate TouchFree’s touchless technology into their target applications as native features. More detailed information, including Quick Start Guides, can be found in the TouchFree Tooling packages for Web and Unity.

TouchFree Service

TouchFree Service is the engine of TouchFree and is required to power both TouchFree Application and developed applications integrated with TouchFree Tooling.

The TouchFree Service converts hand movements, provided by Ultraleap’s hand tracking cameras, into positional data that TouchFree Application (or your own touchless application) can use to represent a cursor on screen.

Everything Else

Air Push

An interaction type. TouchFree’s default interaction method. Users push their hand towards the screen to trigger a click event.

Call to Interact (CTI)

Instructional elements that attract user attention, bring users into position, and teach them how to interact.

Click event

An action triggered by a touchless interaction that would be the equivalent a mouse click.


Abbreviation of Call To Interact.

Gesture control

The use of mid-air movements (gestures) to control a touchless cursor.

Hand Tracking Camera

An Ultraleap Hand Tracking Camera. Either a Leap Motion Controller or a Stereo IR 170.

Hand Tracking Software

The latest release of the Ultraleap Hand Tracking Software.

Hover & Hold

An interaction type. Users hold the cursor still for a short period of time to trigger a click event.

Interaction Type

Different methods for touchless control as defined by specific user behaviours required to trigger a click event. TouchFree 2.1 has three interaction types; Air Push, Hover & Hold and Touch Plane.

Interaction Zone

The 3D area in which the Ultraleap Hand Tracking Camera will track hands.


Leap Motion Controller. An Ultraleap Hand Tracking Camera.

Scroll and drag

An interaction setting offering touchscreen-like behaviour. Emulates the click and drag behaviour of a mouse. With Scroll and drag activated, users can drag and scroll through on-screen content.

Stereo IR 170

Stereo IR 170. An Ultraleap Hand Tracking Camera with a wider field of view, longer tracking range, and slimmer form factor than the LMC.

Touch Plane

An interaction type. Users interact by touching an invisible mid-air plane in front of the screen.