Some tools I use/find useful.
Windows
Linux
Mac
Android
Chrome
Open source audio recorder/editor
A popular voice/chat app.
Web browser full of customizability.
A great Java IDE.
Powerful MongoDB editor.
Open source software for screen recording.
Nice and useful photo editor.
Powerful API Client.
Producitive features for Windows.
Simple but advanced video editor.
A better screenshot system.
Instant messaging app with lots of functionality.
A good media player.
A lightweight code editor with plenty of plugins.
A modern terminal with plenty of features.