Schulrechner

Joris Yidong Scholl | Calculator

7 Downloads 17 Views v1.1 3.04 MB 4.1+

Download APK

(3.04 MB)

Editor's Overview

Schulrechner is a calculator application developed by Joris Yidong Scholl, packaged as a single Android APK of version 1.1 weighing in at 3.04 MB. The package targets Android 4.1+ and above. Below you'll find the publisher's own description, a quick spec sheet, and a short buyer-beware checklist so you know exactly what you're installing before tapping download.

Install Checklist

Only download through the button on this page — never from third-party mirrors or shortened links, which are the most common way malware spreads.
File size is a light 3.04 MB, so it installs quickly even on modest connections.
This build is signed by "Joris Yidong Scholl" — always verify the developer name matches what's listed on the app's official store page before installing an update.
After install, Android may prompt you to allow "Install from unknown sources" — approve only this one install, then revoke the permission in Settings > Apps > Special access.
We link directly to the APK file or the publisher's repository; we do not modify the binary. Always run a virus scan after any sideloaded install.

About this app

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!

Details

Version	v1.1
Size	3.04 MB
Developer	Joris Yidong Scholl
Category	Calculator
Package	io.cardijey.schulrechner
Android	4.1+
Last Updated	Oct 29, 2026
Downloads	7

Frequently Asked Questions

Is Schulrechner free to download?
Yes. The APK file linked from this page is free. The developer may offer in-app purchases once installed, but obtaining the installer itself costs nothing.

What Android version does Schulrechner require?
Android 4.1+ or newer. Installing on older devices may cause crashes or refuse to install.

Is Schulrechner safe to install?
We link to the exact APK published by Joris Yidong Scholl. We do not modify the file. Still, as with any sideloaded app, scan it with a reputable antivirus before opening it, and only grant permissions the app genuinely needs.

How do I update Schulrechner?
Install the newer version on top of the old one — Android will keep your data. If the signature differs, uninstall first (you may lose local progress).

Why is the app not installing?
Common causes: not enough storage, an older Android version than 4.1+, or a conflicting build already installed. Free up space, check your OS version, and uninstall any previous copy before retrying.

How to Download & Install Schulrechner

Tap the Download APK button above and save the file to your device.
Open your device Settings → Security (or Apps → Special access → Install unknown apps) and allow your file manager or browser to install unknown apps for this one file only.
Open the downloaded io.cardijey.schulrechner.apk file from your Downloads folder.
Tap Install and wait for Android to finish.
Open «Schulrechner» by Joris Yidong Scholl and grant only the permissions it actually needs.
Revoke the "unknown sources" permission once you are done installing.

Note: this page hosts or links to the installer only. The application name, icon and description are provided for identification. All trademarks belong to their respective owners.