Startup headed by ex-Apple engineer aims to eliminate smartphone buttons

Sentons, a startup led by chip industry veterans, on Thursday began marketing technology that aims to do away with gadget buttons and said it is working with two smartphone makers in addition to an existing contract with Asus Computer Inc.
Headed by Jess Lee, an engineer who sold his previous company to Apple Inc, Sentons announced a sensor system that uses ultrasonic sound waves to detect touches, presses and swipes on a variety of materials such as the metal edges around a smartphone.
The technology is already being used by Taiwan’s Asus and its partner Tencent Holdings in a phone designed for gamers that was released in China this summer.