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Jonas Lochmann 28a161bbb9
Release 2.1
11 months ago
app Release 2.1 11 months ago
art Initial commit 3 years ago
gradle/wrapper Update buildtools and dependencies 11 months ago
.gitignore Initial commit 3 years ago
LICENSE.txt Initial commit 3 years ago Add F-Droid link to the Readme 3 years ago
build.gradle Remove unused dependencies 11 months ago Add MaxMetaspaceSize to 1 year ago
gradlew make gradlew executable 11 months ago
gradlew.bat Initial commit 3 years ago
settings.gradle Initial commit 3 years ago


(Rechnen = german for calculating)

This is a simple, but configurable mental calculation trainer.



Screenshot of training itself

Screenshot of a part of the configuration screen


old config screen old training screen

  • originally a dark themed App from the age of Android 4
  • for this version, nearly everything of it was rewritten
    • new UI (most changes were made at the config screen)
    • Kotlin instead of Java
    • training logic separated from the UI
    • Room as database abstraction instead of using sqlite directly
    • object serialization using JSON instead of a custom format