Gone From My Sight

A Practical Guide to Using Gone From My Sight on Mac

Gone From My Sight is a macOS app that uses your built-in camera to watch for people approaching your screen, then automatically locks or blurs your display when it detects movement or a face nearby. It's aimed at people who work in shared spaces — coffee shops, open-plan offices, or anywhere someone might walk behind you and look over your shoulder. I've been running it on and off for a few years now, mostly in a co-working setup where the privacy angle actually mattered. The app monitors your camera feed in real time. When it detects a human face or significant motion within a configurable distance from your screen, it triggers an action. That action is usually one of three things: it locks your Mac, blurs the entire screen so nothing is readable, or takes a snapshot of whoever is looking. You can configure all of these in the preferences panel. The detection sensitivity is adjustable, which matters more than you'd think because the default setting will trigger constantly if you have a window behind you that catches passing movement. It also has an idle detection mode. If your keyboard and mouse haven't been touched for a set period, it can auto-lock after a delay. This is the feature most people actually use, because the face-detection side is finicky in practice.

How to Get It Running

You download it from gonefrommysight.com and install the .dmg like any regular Mac app. The first thing you need to do is grant camera permissions in System Settings under Privacy & Security. The installer doesn't always handle this cleanly on newer macOS versions, so if the app launches but never detects anything, check that the camera access is actually enabled. I hit that issue on macOS Sonoma and wasted about twenty minutes before realizing the permission prompt had somehow reset. After installation, open the app and you'll see a simple toolbar icon in your menu bar. Right-click it to access the main settings. The interface is functional if a bit dated. You'll set your detection zone, choose what action to take, and configure the idle timeout. Keep the detection radius narrow if you can. The wider you set it, the more false triggers you get from reflections, TV screens, or anyone walking down the hallway outside your window.

The Face Detection Reality Check

Here's what nobody tells you about the face detection feature: it works fine in good lighting and with a direct line of sight to your camera. It fails completely in low light, with backlighting, or if your camera is positioned at an angle where people approaching from the side aren't captured clearly. Apple's TrueDepth cameras on newer Macs handle this better than the older iSight cameras, but even then, expect about a ten to fifteen percent false trigger rate in a busy environment. My workaround for the false triggers was to disable the motion-based detection entirely and run only the face detection with a minimum dwell time of two seconds. That means the system has to confirm a face is present for two full seconds before locking. It added a tiny delay but eliminated about ninety percent of the accidental locks. I also set the detection zone to a narrow cone directly behind my chair rather than a wide arc, which helped a lot since most of my false triggers came from people walking past my desk laterally instead of actually stopping to look.

Common Pitfalls and What I Wish I'd Known

One thing that catches people out is that the app needs to be running with full privileges. If you put your Mac to sleep and wake it up, the monitoring session sometimes doesn't resume properly. I've had cases where the app appeared active in the menu bar but wasn't actually watching the camera feed. The fix is simple but easy to miss: quit the app completely and restart it after waking from sleep. It takes about five seconds and saves you from the false sense of security. Another issue is conflicting login items. If you have other camera-accessing apps running at startup — Zoom, facial recognition tools, even some webcam overlay utilities — Gone From My Sight can lose camera access because macOS only allows one app to use the camera at a time. I learned this the hard way when the app silently stopped detecting faces after I added a browser extension that also wanted camera permissions. Closing the conflicting app resolved it immediately. The app also doesn't have a built-in whitelist for trusted faces. If someone regularly sits behind you and you trust them, you're out of luck. You'd need to either lower sensitivity or disable the feature around them. There are workarounds using custom detection zones and timing, but they're not intuitive. If a whitelist is important to your use case, you might want to look at something like Camera Shield or just rely on the idle lock feature instead, which doesn't have this limitation.

Performance and Battery Impact

The app consumes a small but noticeable amount of CPU while the camera is active. On an M-series Mac you won't feel it, but on older Intel machines with a built-in camera, you may see a slight fan spin-up. Battery drain is roughly equivalent to having a video call running in the background. If you're on a laptop working away from power, expect maybe five to eight percent extra drain per hour of active monitoring. I usually just turn it off when I'm traveling and rely on the automatic idle lock instead, which uses almost no resources since the camera stays off.

Is It Worth It

It depends on your situation. If you work from home with doors closed, you probably don't need it. If you're in a shared office, a library, or a café regularly, the idle lock feature alone justifies the price for most people. The face detection is a nice-to-have that works adequately but requires tuning. At the price point it's reasonable, though the app hasn't had a major update in a while and the interface shows its age. If you want something more polished with better detection accuracy, alternatives like Lockwatch or even just macOS's own screen lock automation with a third-party launcher might serve you better. But for a straightforward privacy tool that does one thing and does it well once you dial in the settings, Gone From My Sight gets the job done.