A free posture app for your Mac's menu bar
ErgoSense uses the FaceTime camera to spot slouching as it happens, tracks blink rate and eye strain alongside posture, and never sends a frame anywhere.
macOS has the most choice — and the most subscriptions
Unlike Linux, the Mac is well served here. Zen, BLiiNK, Posture Reminder AI, SitApp and Nekoze all run on macOS. The catch is price: Posture Reminder AI is $99.99 a year, BLiiNK has no permanent free tier at all, and Zen's free version is limited enough to be a trial in practice.
Only two Mac apps are genuinely free with no cap — ErgoSense and Nekoze. Nekoze is the better pick if you want something tiny that does exactly one thing. ErgoSense makes more sense if you also care about eye strain, want daily analytics, or use a Windows or Linux machine as well. We lay out the trade-offs honestly in the full comparison, including where ErgoSense loses.
Install on macOS
- 1
Download the .dmg
Apple Silicon (M-series) only, on macOS 12 Monterey or later. There is no Intel build. - 2
Drag ErgoSense to Applications
Open the disk image and drag the app across, then eject the image. Running the app from inside the mounted.dmgworks but will not survive a restart. - 3
Get past Gatekeeper on first launch
macOS will say the app is from an unidentified developer and refuse to open it. Go to System Settings → Privacy & Security, scroll to the Security section, and click Open Anyway next to the ErgoSense message. You will be asked to confirm once. This is a one-off. - 4
Grant camera access
macOS prompts on first use. If you dismiss the prompt by accident, re-enable it under System Settings → Privacy & Security → Camera. Posture detection cannot work without it — there is no fallback mode. - 5
Add it to Login Items
System Settings → General → Login Items, then add ErgoSense. It lives in the menu bar rather than the Dock, so it stays out of the way.
About the Gatekeeper warning. ErgoSense is not notarised, because notarisation requires a paid Apple Developer membership and the app has no revenue. macOS shows that warning for every unsigned app, harmless or not, so it tells you nothing about this one specifically. Verify the SHA-256 checksum published with each release if you want independent assurance.
What macOS does and does not let it see
macOS gates camera access through TCC, so ErgoSense cannot touch the camera until you explicitly approve it, and you can revoke that at any time in Privacy & Security. The green camera indicator light is hardware-wired on every Mac — if the app is looking, you will see it, and no software can suppress that.
Frames are analysed on-device and discarded immediately. Nothing is written to disk, nothing is uploaded, and there is no account to create.
Raise your screen first. The most effective change for most Mac users is not an app at all. A laptop on a desk forces your head down all day; a stand plus an external keyboard fixes more forward-neck posture than any notification will.
Questions
What is the best free posture app for Mac?
ErgoSense and Nekoze are the two genuinely free webcam options on macOS — neither has a paid tier. Nekoze is smaller and simpler: a menu bar app with a cartoon cat that meows when you slouch. ErgoSense additionally tracks eye strain, blink rate and focus time, and runs on Windows and Linux if you use more than one machine. SitApp has a free tier but caps it at one hour of monitoring per day.
Why does macOS say ErgoSense is from an unidentified developer?
Because the build is not notarised with Apple. Notarisation requires a paid Apple Developer Program membership, and ErgoSense is free with no revenue behind it. Gatekeeper shows the same warning for any unsigned app regardless of what it does. You can bypass it via System Settings, or verify the published SHA-256 checksum first if you would rather confirm the download independently.
Does it work on Apple Silicon?
Yes — Apple Silicon is the only Mac architecture ErgoSense currently ships, on macOS 12 Monterey or later. There is no Intel build yet. If you are on an Intel Mac, Nekoze and Zen both still support it.
Can I use my iPhone as the camera?
ErgoSense uses whatever camera macOS presents as the default capture device, so Continuity Camera works if your Mac and iPhone are signed into the same Apple ID and meet Apple's requirements. In practice the built-in FaceTime camera is more than adequate for posture detection — you are tracking shoulder and head position, not reading fine detail.
Will it drain my battery?
Inference is throttled and typically stays under 5% CPU. It is not free, though: any app doing continuous webcam analysis costs more battery than one that does nothing. On a MacBook away from power for a full day you may prefer to run it only during focused work blocks.
Free forever, no Apple ID needed
Not on the App Store, not a subscription, and not tracking you.
Also available for Windows and Linux. See all features.