A proximity-based mutually capacitance-sensitive touchpad that is disposed directly beneath a keypad keymat of a mobile telephone, wherein posts associated with each key pass through a mutually capacitance-sensitive sensor electrode grid of the touchpad such that the keypad posts do not interfere with...http://www.google.com/patents/US20070115263?utm_source=gb-gplus-sharePatent US20070115263 - System for disposing a proximity sensitive touchpad behind a mobile phone keymat
