PARCTab
The PARCTab was a mobile computer designed by Xerox. It was the first device made to meet the concept of ubiquitous computing. The PARCTab was similar in shape, size, and appearance to a PDA. It had a touch screen and a stylus. It had handwriting recognition.
The PARCTab was one of the devices as part of Xerox's PARC program. Roy Want was one of the team members.
PARC coined the term "ubiquitous computing".