Touchscreen has been there for years and popular since the old days of PDAs(personal digital assistant).
More and more smartphones/tablets today are touchscreen-based and these devices are made by Nokia, Sony-Ericsson, Apple, Blackberry, Samsung, HTC and others.
There are many types of touchscreen out there however the common ones are capacitive, resistive and infrared. Have you ever wondered how a touchscreen works and the technology behind it?
Check out the Infographic from Cricket Wireless below.
[Source]– Cricket Wireless
http://www.mycricket.com/community/cell-phone-info/how-does-touch-screen-phone-work