DockDoor vs AltTab: which Mac window switcher fits your workflow
If you've gone looking for a better way to move between windows on a Mac, two names come up again and again: DockDoor and AltTab. Both are free, both are open source, both fix the same core annoyance — Cmd-Tab switches apps, not windows — and yet they solve it in almost opposite ways. This DockDoor vs AltTab comparison lays out where each one shines, where each falls short, and what to reach for if neither quite fits.
Short version: AltTab is a keyboard-first thumbnail switcher; DockDoor turns your Dock into a window previewer. They overlap, but their centers of gravity are different — and which one you'll love depends on whether your hand lives on the keyboard or the trackpad.
What each one actually is
AltTab replaces the Cmd-Tab overlay with a richer one. Hold its shortcut (⌥⇥ by default) and you get a row of live window thumbnails — every window, not just app icons — that you can cycle with the keyboard or click. It's deeply configurable: which windows appear, how they're sorted, how big the thumbnails are, blacklists, multiple shortcut sets. It crosses Spaces, and it's been the community favourite for years. The core app is free and open source under GPL-3.0; a newer, optional AltTab Pro adds power-user extras (more on pricing below).
DockDoor takes a different tack: instead of replacing the switcher, it augments the Dock you already have. Hover an app's Dock icon and you get Windows-style live thumbnails of that app's windows — the preview macOS has never offered natively. From those previews you can close, minimize, or maximize a window directly, swipe between them with two fingers, and it throws in extras like a compact list view, media controls, and calendar peeks. It also includes its own Option+Tab switcher, so it isn't Dock-only. It's completely free and open source, with zero data collection — not even crash reports.
DockDoor vs AltTab at a glance
| AltTab | DockDoor | Let's Switch | |
|---|---|---|---|
| Center of gravity | Keyboard thumbnail switcher | Dock-hover window previews | Minimal keyboard MRU switcher |
| Default trigger | ⌥⇥ overlay | Hover the Dock (+ ⌥⇥) | ⌥⇥ overlay |
| Live window previews | Yes, thumbnails | Yes, on Dock hover + switcher | Yes, in the overlay |
| Dock-hover previews | No | Yes (its signature) | No |
| Ordering | Configurable | By app (the Dock icon) | Most-recently-used first |
| Search / launch apps | Search (AltTab Pro) | Compact list | ⌥Space palette — finds windows and launches apps (Pro) |
| Config depth | Very deep | Moderate | Deliberately minimal |
| Crosses Spaces | Yes | Partly | No (current Space) |
| License | Free / open source (GPL-3.0) | Free / open source | Paid app, free tier (not open source) |
| Price | Free core; Pro $9.99 one-time (or $24.99 lifetime) | Free | Free tier; Pro pay-once |
Facts checked against each project's site in July 2026; verify current details before buying.
When DockDoor is the better pick
Choose DockDoor if your navigation is anchored to the Dock and the trackpad. If you keep the Dock visible, work with a mouse, and often have several windows per app, hovering an icon to peek and click the right window feels completely natural — no shortcut to learn, no overlay to summon. The per-preview close/minimize buttons are genuinely handy for tidying up without switching first. It's the closest thing to the Windows taskbar-preview behaviour many switchers miss.
The trade-off: hovering is a mouse gesture. If you're trying to keep your hands on the keyboard, reaching for the Dock breaks the flow, and DockDoor's own alt-tab, while capable, isn't its main event.
When AltTab is the better pick
Choose AltTab if you want the most powerful, most configurable keyboard switcher and you like to tune things. Nobody offers more knobs: window filtering, sort order, thumbnail size, cross-Space switching, multiple shortcut profiles. It's open source with a large, active community, and it consistently lands on "best Mac apps" lists for good reason. If you'll happily spend twenty minutes in a settings panel to get switching exactly how you want it, AltTab rewards that.
The trade-off is the flip side of the same coin: it's a lot of surface area. Some people just want to flip to their last window and get on with it, and AltTab's depth can feel like more than they signed up for. Note too that AltTab Pro ($9.99 one-time for current-version updates, or $24.99 lifetime; 14-day trial; up to 3 devices) now sits behind some of the newer extras like built-in search — the core switcher stays free, but the shiniest bits are paid.
The third option: minimal and MRU-first
Both apps above are excellent, and if either fits, use it — free and open source is hard to argue with. But there's a gap between them: DockDoor is mouse-centric, AltTab is powerful-but-heavy, and neither is built around the one pattern most switching actually follows — most-recently-used order.
That's the niche Let's Switch fills. Hold ⌥⇥ and it flips through your windows newest-first, with a live preview of each, across apps and monitors — release on the one you want. No app grouping, no settings marathon: the window you were just in is one tap away, the one before that is two. Cycling a single app's windows is a separate free move (⌥`). And its Pro ⌥Space palette does something neither rival does — fuzzy-find any open window and launch any installed app from the same box, so it doubles as a launcher.
Being honest about the trade-offs: Let's Switch is newer than both veterans, it is not open source, and it works within your current Space (AltTab crosses Spaces). What you get in return is a deliberately small tool — menu-bar only, no Dock icon — that's pay-once with no account, no subscription, no telemetry, and up to 20 devices per key. If AltTab's depth is more than you want and DockDoor's Dock-hover model isn't how you work, minimal-and-keyboard-first is the third road.
Frequently asked questions
Is DockDoor or AltTab better? Neither is universally better — they optimise for different hands. AltTab is the better keyboard switcher; DockDoor is the better Dock-and-trackpad previewer. Pick by how you actually navigate.
Are DockDoor and AltTab really free? Yes. Both are free and open source. AltTab has an optional paid Pro tier for extras, but its core switcher stays free; DockDoor is entirely free with no paid tier.
Can I run both at once? You can, but they'll overlap on the alt-tab shortcut, so you'd typically use DockDoor for Dock previews and let something else own ⌥⇥. Pick one switcher to avoid fighting over the same keys.
Do any of them switch between Spaces? AltTab can switch across Spaces. DockDoor works mainly within the current Space, and Let's Switch stays within the current Space by design. If cross-Space switching is essential, AltTab is the safe choice.
Which is the most keyboard-friendly? AltTab and Let's Switch are both keyboard-first; DockDoor leans on the mouse for its signature Dock previews. Between the two keyboard tools, AltTab is the most configurable and Let's Switch the most minimal.
Still weighing your options? The Let's Switch page shows the ⌥⇥ overlay and the ⌥Space palette in action, and the blog has deeper guides on Mac window switching if you want to go further.