No magic. Just macOS,
used properly.

Crumble Bar

The taskbar itself, the live window peek, the Start menu and the system tray.

The bar No permission

Crumble Bar is a native AppKit panel pinned to the bottom of the screen. The app runs as a background agent, so it never takes a slot in the Dock or the ⌘Tab switcher, and the panel is non-activating: clicking a taskbar button never steals focus from the app you are working in. Pinned apps and the list of running apps come from the system workspace, which any Mac app can read.

Live window previews Screen Recording

Hovering an app asks Apple's ScreenCaptureKit for a thumbnail of each of that app's windows. Thumbnails refresh on a light timer (about 0.7 seconds) rather than a continuous video stream, which keeps CPU use down even with many windows open. This is the same framework screen-sharing apps use, which is why macOS files it under Screen Recording. Every frame is rendered and thrown away on your Mac; nothing is recorded, stored or uploaded.

Click a thumbnail, raise that window Accessibility

macOS has no public "bring window 3 of Safari forward" call, so Crumble Bar uses the Accessibility API: each window is addressed as an accessibility element, and raising or closing it is a standard accessibility action. This is the same machinery macOS provides to assistive tools, and it is the backbone of every serious window manager on the platform.

Keeping windows above the bar Accessibility

The Dock can reserve screen space with a private system call; third-party apps cannot. So Crumble Bar watches window geometry through the Accessibility API and gently resizes any window whose bottom edge dips into the bar's strip. It is the same technique Rectangle and yabai use. Native full-screen apps own their entire Space, so there the bar auto-hides instead and slides back when you nudge the pointer to the bottom edge, exactly like the Dock does.

Start menu, hotkey and ⌘ tap Accessibility

The ⌃⌥Space chord is a standard system hotkey and needs no permission. The Windows-style option, tapping a bare ⌘ key, cannot be a hotkey, so Crumble Bar watches modifier keys with passive event monitors: they observe, they never intercept, so a bug here can never swallow or delay your typing. A tap fires only when the key is pressed and released on its own; ⌘C, ⌘-drag and a held ⌘ never trigger it. Seeing keys while another app is frontmost is what requires the Accessibility grant. If your Start action is Spotlight, the app synthesizes a ⌘Space keystroke, which also runs through Accessibility.

Right-click jump lists No extra permission

Jump-list actions such as Chrome's New Incognito Window are sent as the app's own keyboard shortcut (for example ⌘N) rather than by scripting the app. That choice is deliberate: scripting other apps would trigger a separate Automation prompt for every single app. Keystrokes ride on the Accessibility grant you already made.

Quick Settings Bluetooth Location Automation

The Windows 11 style flyout is assembled from three optional grants, and each degrades gracefully if you skip it:

• Wi-Fi list: network names come from CoreWLAN. Since macOS treats nearby network names as location data, reading them requires Location Services. Crumble never computes, stores or sends your location; the grant purely unlocks the names.
• Bluetooth list: paired devices are read through IOBluetooth, and macOS shows its Bluetooth consent dialog once.
• Dark Mode, AirDrop and power options: toggled through Apple's documented scripting hooks in System Events, which macOS gates behind the Automation permission.

Copy text from screen Screen Recording

Press ⌃⌥T, drag a rectangle over anything on screen, and the text lands on your clipboard. ScreenCaptureKit grabs just the selected region (the same grant as the previews) and Apple's Vision framework runs the OCR entirely on-device. No image or text ever touches the network.

Crumble Snap

Rectangle-style snapping: drag zones, keyboard shortcuts, the throw grid, edge stashing and workspace layouts.

How snapping works Accessibility

Every Snap feature is a combination of the same two ingredients. Passive event monitors watch your drag or shortcut, and the Accessibility API moves and resizes the target window. macOS deliberately routes "control another app's windows" through Accessibility, which is why Rectangle, Magnet and every other snapping tool asks for the identical grant.

• Drag snapping: drag a window to an edge or corner and a preview zone lights up; release to snap to halves, quarters or thirds.
• Keyboard shortcuts: every zone has a chord, with size cycling, restore-to-previous-frame, and moving windows between displays.
• Throw grid: hold ⇧ mid-drag for a grid overlay and file the window into any cell.
• Custom targets: define your own named regions and snap to them like any built-in zone.
• Edge stashing: push a window off the left or right edge; a sliver stays visible and it peels back on hover.
• Workspace layouts: save the position of every window as a layout and recall it with one shortcut.

Crumble Ask

The optional Claude panel. This is the one feature that talks to a server, so here is exactly what it sends.

The panel Accessibility

Press ⌥Space in any app and a chat panel opens on your desktop. The trigger uses the same passive modifier monitoring as the Start key, and the panel is the same non-activating panel type as the bar, so it opens without yanking focus away from your work.

What gets sent, and what does not

When you submit a prompt, the text you typed is sent over TLS to Anthropic's Claude API and the reply streams back. That is the entire exchange: no screenshots, no window titles, no clipboard, no keylog. Quick calculations are answered by an on-device calculator before any request is made, so "48*365" never leaves your Mac at all.

Ask is an add-on: it unlocks with a product key from either With Ask plan, and the entitlement travels inside the key itself.

Licensing & trial

The 7-day trial unlocks Crumble Bar and Crumble Snap with no account and no credit card. The trial clock is anchored in your Mac's Keychain, not a server. Entering a product key validates it with the licensing service and stores the result locally; subscriptions re-check periodically, while one-time licenses are yours to keep. Keys cover all the Macs you personally use.

Permissions, feature by feature

Two grants are required for the core experience; three are optional and only feed Quick Settings. All five live in System Settings → Privacy & Security and can be revoked anytime; features simply switch off rather than break.

What leaves your Mac

Three things, each one initiated by you:

• Product-key validation, when you enter or renew a license.
• Crumble Ask prompts, sent to the Claude API when you press return in the panel.
• Feedback, if you choose to send a feature request or bug report from the app.

Everything else, window thumbnails, OCR, snapping, your pinned apps and settings, is processed and stored on-device. There are no analytics and no tracking on the app or this site.

Changelog

Every notable change, newest first.