The technology called Hairware, invented by Katia Vega of the Pontifical Catholic University of Rio de Janeiro, Brazil, uses a hair-wearable switch that can discreetly activate apps by touching it a set number of times.
Users of the technology would wear natural-looking hair extensions that include conductive hair filaments. When touched in a specific way, the filaments discreetly activate a smartphone app.
Vega said that the technology can be used by a woman who is feeling threatened to broadcast her location, or activate a preset emergency text message, without visibly using the phone.
An Arduino microcontroller and a bluetooth radio in a hairclip provide the system's intelligence and connectivity, with an algorithm learning over time when the user has intended to trigger an action, 'New Scientist' reported.

The hair's ability to store electric charge changes when touched and this can be used to set controls. For example, stroking it once activates one app and touching twice launches another.
Vega has plans to extend Hairware and turn beards into active app controllers too.
She presented the technology at IUI 2015, a user interface conference in Atlanta, Georgia, last week – where delegates used Hairware to take selfies.