How📱Pinephone brought a 🖩 HP42C calculator clone into my life

I have a Pinephone Braveheart edition. When I got it, the only so-so usable OS was Ubuntu Touch. When browsing an OpenStore I came by Enter 41 app, which emulates HP41C calculator.

I have installed it, and luckily I also started googling some information about it. I have learned about the fascinating world of old HP calculators and their fans. While doing my research I have found an emulator of a slightly newer (but still very archaic) HP42S called Free42.

I immediately fell in love with it and installed it on my Android phone as well as my home and work computer. It is open source, it is a rewrite of the original HP code, so completely legal, fair and made with great love. I also like the capabilities of HP42S much more compared to its predecessor HP41C.

I have downloaded old manuals and new manuals, some programs, learned to use Reverse Polish Notation (RPN) input logic and started to use it on a daily basis.

While googling more information about Free42, I have also learned about Swiss Micros' DM42, which is a dedicated calculator device running Free42.

My wife originally objected to the relatively high price of the thing (199 CHF), but I knew, that it is a must. So after some negotiating and cancelling certain Kickstarter pledges, I bought it to myself as a birthday present and I have never regretted doing it.

It is very well-built, and it is beautiful as a physical object. At the same time I find the software a well-balanced mix of rich features and ease of use, which is usually quite challenging to achieve.

It is an object of different era - the manuals are more like textbooks on algebra, physics and programming, the case is made to last, yet it is light and sleek, it fits very well in hand.

Throughout my whole career in first Market Research and then Data Science, I have always used calculators as means of quick estimates, educated guesses, etc.

With DM42 it just got to a completely new level. I have even dug out my old Casio fx-7700GE, that I got from my parents 25 years ago, when entering the university, but though it is 10 years younger compared to the original HP42S and much more advanced in terms of graphics and programming, it just cannot compare.

I find it similar to Gemini in certain philosophical aspects. So it is no wonder that I had to write this post here.

For comments and 2 photos of the actual calculator I own, please see this toot: