GreenSignal gives you a quick confidence check before every video call. Run a pre-call check for your camera, microphone, speakers, room noise, and network connection. Instead of showing a complicated diagnostics dashboard, GreenSignal gives you a simple answer: you're ready, or here's the one thing to fix. Everything runs locally on your computer. No accounts, no tracking, no cloud processing, and no recorded audio or video. Free for macOS and Windows.