Semantik
Semantik is a free and open source program for creating mind maps for KDE, which helps you create presentations, dissertations, essays, reports
Qalculate!
Qalculate! – free and open source, cross-platform, simple yet powerful and versatile calculator
Elcalc
Elcalc is a free and open source, cross-platform simple calculator on Electron
Pro Office Calculator
Pro Office Calculator is a free and open source, simple calculator designed to perform simple arithmetic calculations
theCalculator
theCalculator is a free and open source, simple calculator that supports some scientific features
Azote
Azote is a free and open source wallpaper manager and color matching tool for Sway, i3, and WM
Fondo
Fondo is a free and open source program for finding wallpapers on Unsplash.com and setting them as your desktop background
KColorChooser
KColorChooser is a free and open source small and simple program for mixing colors and creating custom color palettes
Totem
Totem is a free and open source, simple movie player for the GNOME desktop
Parole
Parole is a free and open source, modern simple media player for the Xfce graphics environment