The Official NASA Task Load Index (TLX) App, widely regarded as the gold standard for measuring subjective workload across a wide range of industries, enables researchers to easily perform assessments on operators working with various human-machine interface systems.

By incorporating a multi-dimensional rating procedure, the NASA TLX derives an overall workload score based on a weighted average of ratings on six sub scales:

∙ Mental Demand
∙ Physical Demand
∙ Temporal Demand
∙ Performance
∙ Effort
∙ Frustration

Originally developed as a paper and pencil questionnaire by NASA Ames Research Center’s (ARC) Sandra Hart in the 1980s, the NASA TLX is the benchmark against which the efficacy of other measures, theories, or models are judged. The NASA TLX has been successfully used around the world to assess workload in various environments such as aircraft cockpits; command, control, and communication (C3) workstations; supervisory and process control; and simulations and laboratory tests.

The NASA TLX app for iOS dramatically increases the outreach and accessibility for the research and development community, and enables mobile and contextual assessments (e.g., in an airplane cockpit during/after flight, rather than at a desktop computer in a lab). It offers several key features that benefits both researchers and participants:

The NASA TLX has been designed to ensure the privacy of research participant data. The NASA TLX anonymizes all results and does not send any personal identifiable information (PII) to any data servers.

Location Flexibility
The NASA TLX app can be used anywhere, even without a network connection, so researchers can have participants complete a NASA TLX evaluation in the field, outside the confines of a desktop office environment. The NASA TLX results are calculated on the device, and, once a network connection is available, collected data can be securely uploaded to servers for analysis. This frees researchers from being burdened by the task of tracking individual paper forms.

Simple Study Setup
Researchers can set up studies quickly and reduce typing on the NASA TLX app by scanning a pre-generated QR code from within the app, which automatically populates the study name, subject ID, and trial number in the app.

What’s New

Version 1.0.3

- Requires iOS 10.0 or greater
- Added the ability to launch the NASA TLX app from other NASA research apps
- Minor iPad layout issue fixes

Ratings and Reviews

4.4 out of 5
7 Ratings

7 Ratings

QuantumFe ,

Great app helps our research

This is a truly great app to help us assess the workload in a easier and faster way. Just one complaint: would you please rearrange the results history so that I could find my results quicker. The current arrangement seems to be randomized.

juanAntonio95 ,

When trying to share data app freezes

Whenever I try to export data to either my email or a file in my phone the app freezes. Also, there is no way of selecting multiple files to export

App Privacy

The developer, NASA, has not provided details about its privacy practices and handling of data to Apple.

No Details Provided

The developer will be required to provide privacy details when they submit their next app update.


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