Extended emulator of МК 61/54 vs Schulrechner
Side-by-side comparison of two open source alternatives
Extended emulator of МК 61/54
МК 61 was the best seller of all USSR programmable calculators of 1980-s (B3-34, MK-54, MK-56, MK-61, MK-52). Calculators are emulated on microcode level so they behave exactly like the original devices, including all non-documented features and inaccurate calculations. For ease of use application features saving and loading emulation states. This app's emulation engine Java code is based on C++ source of Felix Lazarev's emu145 project. Emulation was highly optimized for speed and should run in real time on any phone. It's an extended version of the original emulator МК 61/54 by Stanislav Borutsky (https://play.google.com/store/apps/details?id=com.cax.pmk). This version allows to export/import programs from external files and contains some UI improvements. Hint 0: you can found the list of all tips in the About dialog Hint 1: touch calculator's indicator to toggle slow/fast mode. Indicator's blinking looks better in slow mode. Hint 2: you can choose between MK-61 and MK-54 using menu option that becomes visible when calculator is switched off. Hint 3: with the menu "Import" you can import programs from external files, several such programs you can find in https://xvadim.github.io/xbasoft/pmk/pmk.html Hit 4: you can open menu by long tap on the "Вкл" label.
Schulrechner
This is a very early version in development. Unlabeled buttons will be implemented in the future, and bugs may be frequent. If you experience issues or have feature requests, please file an issue (link below). Frustrated by the lack of free, open-source scientific calculators that feel like the ones I am used to, I decided to reverse-engineer my old calculator from school. With features like: - input of complex equations, - output as fractions as well as decimals, - result storage and reuse, - selection and editing of equations from input history, - and support for implicit multiplication (like 5π instead of 5*π), this calculator produces math that looks like the math on your paper. That makes it much more suitable for higher-level math in school and university—especially if you've grown accustomed to this kind of interface from a young age and just forgot your calculator at home. Some additional features include: - A well-established open-source math.js library as the math engine—so you’re not relying on some sketchy, hand-rolled math logic (just my sketchy hand-rolled input method 😛) - A familiar, intuitive design - 100% offline usability and fully open source - Written entirely in HTML, JS, and CSS, which means: + inherently cross-platform and also available as a website and Flatpak + easy for other web developers to contribute + admittedly a bit heavy for a calculator. If you're interested in helping make a lighter version (Flutter, Kotlin, etc.), you're very welcome!
| Feature | Extended emulator of МК 61/54 | Schulrechner |
|---|---|---|
| License | GPL-3.0-only | GPL-3.0-only |
| Install sources | F-DroidGitHub | F-DroidGitHub |
| Categories | CalculatorProductivity | CalculatorProductivity |
| Features | Ad-FreeOpen SourceNo Tracking | Ad-FreeOpen SourceNo Tracking |
| Platforms | Android | Android |
| Website | ||
| Source code |