Running a Demo Loop on a Booth MacBook: Keep the Video, App or Dashboard Visible All Day, Block Every Key and Click, Unlock With Touch ID Between Conversations

A MacBook on a booth table is the most convenient demo screen there is and the least defensible. It is at hand height, it has a keyboard facing the aisle, and the person who set it up is usually three metres away talking to someone else. Over a day at a trade show, a hackathon table or a reception desk, the demo video gets paused by a curious finger, someone opens Spotlight to see what is on the machine, a child finds the Dock, and at least once the display goes to sleep and the whole thing turns into a black mirror while the booth is busiest.

The built-in answers do not fit. The macOS lock screen hides the demo. Kiosk-style tools built for iPads do not exist in the same form on a Mac. A guest account still lets people type. What you want is specific: the demo app, video or dashboard stays on screen and keeps running, the display never sleeps, and every key, click and trackpad gesture is ignored until you come back. This post is how to set that up with VibeLock, what a visitor can and cannot do while it is locked, and the handful of things to prepare the night before so the booth runs itself.

What a booth Mac needs that a desk Mac does not

• The screen must stay on for hours. A desk lock can let the display sleep; a demo cannot. VibeLock holds a macOS “no display sleep” assertion while locked and releases it on unlock, so the demo is visible from the aisle all day.
• Only the demo may be visible. Your email, Slack, the deck with next quarter's numbers and the desktop full of files should not be one swipe away. While locked, every app that is not on your Visible While Locked list is hidden, a sweep every two seconds re-hides anything that tries to come back, and an opaque backdrop covers the desktop and its files.
• Nothing a visitor does with their hands may change the screen. A session-wide event tap swallows every key press, modifier, click, drag and scroll before any app sees it. Spotlight, Force Quit and ⌘Q are blocked system-wide, so the demo app cannot be quit and the file search cannot be opened.
• You must be able to get back in quickly between conversations. Touch ID unlocks it; your normal Mac login password is the fallback, checked locally against your account.

Setting up the demo loop

1. Build the loop first. Put the demo in a state that runs without input: a video on repeat in QuickTime or VLC, a slide deck in auto-advance with looping turned on, a dashboard that refreshes itself, or your own app in a demo mode. Test that it runs for ten minutes without asking anything of you. VibeLock blocks input; it will not click Next for you.
2. Install VibeLock and grant Accessibility once. Download the DMG from your Whop purchase, drag it to Applications, launch it, and click the lock icon then Lock. macOS asks for the Accessibility permission that input blocking needs; grant it in System Settings, Privacy & Security, Accessibility, and click Lock again. That is the only permission it asks for, and it needs no network, no account and no files. Do this at the office, not at the booth.
3. Set the visible list to exactly the demo. Menu bar, Visible While Locked, and tick only the app running the loop. Terminals, VS Code and the AI desktop apps are pre-allowed because VibeLock is built for developers; untick anything that is not part of the demo. Visible means watch-only: it stays on screen and nobody can type into it.
4. Leave Accessible While Locked empty. Accessible apps can be used while locked, which is the pair-session feature and exactly what you do not want on a public table. The list is empty by default; keep it that way.
5. Turn on a Focus mode and plug in. Notification banners are drawn by macOS, not by the hidden apps, so a Slack preview can still appear over the demo; a Focus or Do Not Disturb mode stops that. Power matters because the display will not sleep for as long as you are locked.
6. Start the loop, lock, walk away. Lock from the menu bar. Everything else hides, input dies, the display stays awake, and the demo keeps running. Fullscreen the video first if you want the cleanest look; fullscreen windows of visible apps stay exactly where they are.

What a visitor can and cannot do

Worth knowing precisely, because booths attract people who try things. With the demo locked, a visitor who presses keys gets the unlock shield, a near-opaque full-screen panel on every display that covers what is behind it; pressing Esc dismisses it and returns to the watch-only view. Clicks and scrolls are swallowed. The pointer still moves, which looks alarming and does nothing. Media, volume and brightness keys are system events that VibeLock's tap does not intercept, so expect a visitor to be able to mute the demo or dim the screen; glance over when you walk past. Three- and four-finger trackpad swipes between Spaces cannot be blocked by any event tap, so if a swipe lands on a Space showing a blocked app, an opaque shield covers it until the swipe goes back.

Two physical limits remain, and they are the same for every lock app on a Mac. A short press of the power or Touch ID button can sleep or lock the machine, and a long press forces a shutdown; both land at the real macOS login screen, so nothing is exposed, but the demo stops. And closing the lid sleeps the Mac; VibeLock keeps the display awake but does not override lid-close sleep. If the booth layout lets people reach the lid or the power button, put the Mac on a stand behind the table with only the screen facing the aisle, or drive an external display with the Mac plugged in and the lid closed, which macOS keeps awake on its own in that configuration.

The screen itself is, by design, readable: anyone can see what the visible app shows. That is the point of a demo, but check the loop for anything you would not put on a poster, including browser tabs and notification history, before you leave. The full list of what is and is not intercepted is in the security model.

Between conversations: the thirty-second unlock

The reason this works for a whole day is that getting back in costs nothing. Press any key, touch the Touch ID sensor, and the shield is gone; every app you hid comes back exactly as you left it. Show the visitor the real thing, answer their question, start the loop again, lock, and step away. If your Mac has no Touch ID, your login password in the shield does the same job; after five wrong attempts the field pauses for thirty seconds, which is a feature on a public table.

If you want a colleague to be able to drive the demo while you are away without giving them your password, the accessible tier exists for that: mark the demo app accessible and they can click through it while everything else stays locked. Just remember that an accessible app is usable by anyone at the keyboard, not only the colleague; we described the trade-off in letting a colleague approve a prompt without unlocking.

The night-before checklist

• Demo loops for ten minutes with no input.
• VibeLock installed, Accessibility granted, locked and unlocked once at the office.
• Visible While Locked contains only the demo app; Accessible While Locked is empty.
• Focus mode on; energy settings irrelevant because VibeLock holds the display awake, but the charger is in the bag.
• Browser tabs, Dock badges and desktop files cleared, because the backdrop hides the desktop but not what the demo app itself shows.
• Lid and power button out of easy reach, or an external display with the Mac plugged in behind the table.
• Someone besides you knows the login password, in case the Mac restarts.

When the normal lock screen is right instead

VibeLock is a strong deterrent against the casual, opportunistic poking that a booth attracts. It is not a replacement for the macOS login screen against a determined person with time, tools or remote access, and it says so in its own documentation. If the Mac will be left overnight on the stand, lock it properly with ⌃⌘Q or take it with you; the demo loop is for the hours you are nearby, not the hours you are not. And if the demo needs visitors to interact with it, you do not want a lock at all; you want a demo build that cannot reach anything else, which is a different project.

For the same idea in other rooms, see locking a Mac during a presentation and keeping a video playing while the Mac is locked.