MacTap is a free, open-source macOS menu bar app that turns knocks on your MacBook chassis into shortcuts. One, two, or three knocks copy, paste, accept an AI suggestion, take a screenshot, control media, or anything you map. It reads the accelerometer inside the unibody (the same sensor that detects if your laptop is falling) and classifies knocks on-device. Nothing gets uploaded, no account, no network calls. Just a small native Swift app sitting in your menu bar.

Hey PH! Jaskirat here. I posted MacTap on X yesterday as a joke — "made a dumb little mac app" — and woke up to 400k views, 1,573 likes, and 3,000+ downloads. So here it is on Product Hunt. The idea is simple: your MacBook already has an accelerometer sitting inside the chassis doing nothing 99% of the time. MacTap hijacks it to detect sharp knocks, one, two, or three, and maps them to whatever you want. Copy, paste, accept the AI suggestion, screenshot, lock, play/pause. No keyboard needed. It's native Swift, lives in the menu bar, and everything runs on-device. MIT open source. Happy to answer any questions, about the knock detection, the sensor pipeline, the privacy model, whatever. Knock away. 🍎

mactap

Knock your MacBook to run shortcuts

Knock your MacBook to run shortcuts