Is the macOS app signed and safe to open?

Yes. Every macOS build is signed with an Apple Developer ID and notarised by Apple, so it opens with a normal double-click — no right-click workarounds, no security warnings. It still runs entirely on your machine and never phones home.

Windows SmartScreen popped up. What do I do?

Click More info, then Run anyway. SmartScreen flags apps it has not seen widely downloaded yet; the warning clears on its own as more people install it. The app is tiny and runs locally — it never phones home.

Will it close apps with unsaved work?

Yes — everything closes; that is the point. Each app is asked to quit properly first, so your next launch is clean (no crash-recovery prompts), but anything still open a couple of seconds later is force-closed, unsaved work included. Save what matters before you fire it.

How do I set the global hotkey?

Open the menu-bar icon, then Preferences, then Shortcut, and press the key combination you want. Pick something deliberate so you never trigger it by accident.

Is it really free? What is the catch?

No catch. It is genuinely free, with no account and no ads. Anonymous usage statistics and crash reports help us improve it — nothing personal ever leaves your machine.

What data does the app collect?

Anonymous usage statistics and crash reports, used solely to improve the app: which features are used (for example, how many apps a sweep closed), the app version, operating system, and language — plus a crash report if the app itself crashes. Events carry a random install ID, never your name or anything about the apps, files, or windows on your machine. Nothing is sold or shared.

How do I uninstall it?

Quit it from the menu bar, then drag the app to the Trash (macOS), uninstall from Apps & Features (Windows), or remove the package (Linux). It leaves nothing lingering behind.

Close All Apps: Keyboard Shortcut vs One Click

People search for a “close all apps” keyboard shortcut expecting one to exist. Short answer: neither macOS nor Windows ships one. Here’s what the operating systems actually give you, how close you can get with scripting, and when a dedicated button beats a shortcut.

What the OS actually gives you

macOS

Cmd+Q — quits the current app only.
Cmd+Tab then Q (holding Cmd) — quits apps one at a time from the switcher. The closest built-in thing to a loop.
Cmd+Option+Esc — the Force Quit dialog: pick one app, hard-kill it.

Windows

Alt+F4 — closes the active window only.
Ctrl+Shift+Esc — opens Task Manager; ending tasks is manual and forceful.
Win+D — hides everything (shows desktop). Nothing closes; it all comes back.

That last one matters: minimizing is not closing. The apps still hold memory, still play notification sounds, and still appear the moment you Alt+Tab during a screen share.

Building your own shortcut

On macOS you can wrap a quit-all AppleScript in Automator or the Shortcuts app and bind a hotkey — the script and its caveats are in our Mac guide. On Windows the equivalent is a PowerShell or AutoHotkey script around taskkill, where you maintain the exclusion list yourself — one wrong pattern and you’ve closed your clipboard manager or killed Explorer. Both are real options for people who enjoy maintaining scripts. Both break in small ways as the OS changes.

Shortcut vs button: the actual difference

A shortcut you build is invisible — you have to remember it exists, remember the binding, and trust the script under it. A tray button is visible — it’s sitting there when the meeting starts in 30 seconds and your desktop is chaos.

Captain Kill Switch is that button: one click in the menu bar or system tray, every app gets a clean close request, everything is gone within about two seconds, and system processes are protected by an allowlist on all three platforms (macOS, Windows, Linux). No script to maintain, free, auto-updates.

Honest fine print:like any close-everything mechanism that doesn’t stop for dialogs, unsaved work closes with everything else. Save first — the button is for the moment after.

Bottom line

There is no built-in close-all shortcut on any desktop OS.
The built-in loops (Cmd-Tab+Q, Alt+F4) are fine for a few apps, slow for many.
DIY scripts work if you enjoy owning the edge cases.
If you do this often, put a real button in the tray — download it freeand the “shortcut” becomes one click.