SayIn turns your phone into your computer's input pad. Type or dictate on your phone, tap send, and the text lands right at your computer's cursor — zero app install on the phone, pure LAN WebSocket, one npm command to start. Built for Mac Mini users without a mic, vibe coders who think faster than they type, and anyone tired of copy-pasting text between devices. Open source (Apache-2.0), no account, no cloud, no subscription.