Mobile Apps 1990s style!
With all the sophisticated mobile computing devices currently available it's easy to believe that mobile apps have only been around for a few years. In fact arguably the first pocket-sized mobile computer was the 1980 Sharp PC1211, also sold as Radio Shack's TRS-80 Pocket Computer. It was the first mobile computer I owned and was very exciting, having around a kilobyte of memory!
A Psion 3c mobile computer at the National Museum of Computing.
Over the few decades since then mobile computing devices have gone from strength to strength. Therefore I thought I'd write this page as a bit of nostalgia based around apps for the Psion 3 series that I wrote between 1996 and 2000. As well as helping add to the history of mobile computing, hopefully this page will also prove useful to anyone who still has an old Psion device. It's possible to edit the code on a Psion device too, so if you're really into these amazing old devices you may be able to make a version for use on other Psion models.
Chess Recorder for the Psion 3 Series
Chess Recorder was a fun app for anyone interested in playing chess. It allowed users to record chess games step by step and save them for later study. It even included a graphical chess board with realistic graphics for each piece. As you stepped through the game the board showed the actual position of each piece, and the text even showed the value of the pieces each player had left. Maybe if I'd been less interested in mobile device programming, and more interested in practicing, I might be a better chess player now ;)
Chess Recorder was a shareware program but is now free. To unlock all the features you can use the registration code 1103-5768-1533-Z1B3 in the program on your Psion device.
Click here to download Chess Recorder for the Psion 3 Series. The download includes an e-manual to explain how everything works.
Drainage Calculator for the Psion 3 Series
One of the things that excited me about mobile computing, right from the start in the early 80s, was the potential for writing time-saving technical apps. Drainage Calculator was intended to do just that, allowing calculation of flows and pipe sizes for surface water and foul sewers, and was distributed on a major PC magazine cover disc in 1999. The version provided here is actually v2, which included the ability to calculate flows from buildings based on the number of toilets, sinks, and similar items, based on a probability of flow method.
Investment Tracker for the Psion 3 Series
Since the dawn of mobile computing people have been using pocket devices to monitor the value of their investments. Investment Tracker allowed users to do that on a Psion 3 series device, inputting things like share prices as they were published, for each of their investments. The app also allowed each investment to be graphed to show how well it was performing, including relative to stock market trends. This was a large and sophisticated mobile app for its time, and all the code was written on the device using the small, but perfectly designed, Psion keyboard.
Investment Tracker was a shareware program but is now free. To unlock all the features you can use the registration code 1103-5768-1999-Z1B3 in the program on your Psion device.
Click here to download Investment Tracker for the Psion 3 Series and here to download a later update to tracker.lib for minor bugs. The main download includes an e-manual to explain how everything works.