- The Psion 1, introduced in 1984, is considered the first personal digital assistant. The Psion could store addresses and phone numbers, keep a calendar and included a clock and a calculator.
- Apple introduced the Newton Message Pad in 1993 and set off the explosion of development in PDAs. The Message Pad itself didn't win over many customers and was dropped in 1998, but it showed that there could be a market for such devices.
- More than 70 percent of the PDAs that have been sold are from Palm Computing.
- The world's smallest PDA is a wristwatch-size model called onHand, made by Matsucom. It weighs about 2 ounces.