PiP is a free, open-source Mac utility that floats any window — or a cropped portion of it — above all other applications as a persistent picture-in-picture overlay.
What is PiP?
PiP is a lightweight macOS app that captures a live mirror of any running window and pins it in a frameless, always-on-top panel that stays visible no matter what else you do on your Mac. Think of it as borrowing the picture-in-picture trick Safari uses for video — except it works on any window: a Slack thread, a reference spreadsheet, a terminal session, a Figma canvas, whatever you need in your peripheral vision while your main display is occupied.
The project is open-source and hosted on GitHub, which means no App Store gatekeeping, no subscription nag screen, and no telemetry — just a small, focused tool that does exactly one thing.
What does PiP do best?
PiP excels at keeping a live window mirror in view without disrupting your primary workflow. I use it constantly when referencing API documentation while writing code in a full-screen editor, or watching a video call participant while a presentation fills my screen.
- Any window, not just video. Unlike macOS's native PiP, which only works with qualifying video players, this app mirrors any application window — browsers, terminals, productivity tools, design apps.
- Crop to a region. You can drag-resize the overlay to expose only the part of the source window you care about, hiding clutter and saving screen real estate.
- Adjustable opacity. The overlay can be made semi-transparent so it doesn't completely obscure whatever is behind it.
- Click-through mode. Interactions can pass through the overlay to the window underneath, so the floating panel never traps your clicks.
- Always-on-top persistence. The overlay survives workspace switches, full-screen apps, and Mission Control transitions — it genuinely stays put.
Is PiP free?
Yes — PiP is completely free to download and use. It is an open-source project distributed under a permissive licence on GitHub, so there is no premium tier, no in-app purchase, and no expiry. Installation is typically done via Homebrew Cask (brew install --cask pip) or by building from source.
Who should use PiP?
PiP is best suited for power users who routinely manage information from multiple sources simultaneously and find traditional split-screen layouts too rigid. Developers who monitor logs while editing code, video editors who want a client-playback reference beside their timeline, and remote workers who need to watch a shared screen during a call while still typing freely — these are the people who get the most out of it.
If you only ever watch YouTube in Safari and are happy with the browser's built-in PiP button, this tool is probably overkill. But if you have ever wished you could pin any window as an always-visible thumbnail, PiP is the exact answer.
How does PiP compare to other always-on-top tools?
The closest alternatives are Mango 5Star's Mosaic and Overflow 3, but those are window managers, not window mirrors — they arrange windows, they do not float a live copy above everything else. Permute and HiDock are in a different category entirely. The only real functional peer is macOS's own PiP implementation baked into Safari and some media players, but Apple's version is locked to video content from supported sources. PiP-the-app has no such restriction, making it uniquely positioned for non-video reference use-cases.
On the trade-off side, because PiP is a community project rather than a commercial product, the UI is minimal and configuration lives in right-click menus rather than a polished preference pane. Users comfortable with developer tools will feel at home; those expecting a Setapp-quality interface may find it spartan.
What are the best PiP alternatives?
If PiP's minimal interface isn't your style, a few paid alternatives are worth considering. Steuererklarung's Lungo and One Switch are not direct equivalents, but Rottenwood's Window on Top and various AppleScript-based always-on-top hacks offer similar functionality with varying polish levels. For video-only use cases, macOS Safari's native PiP or the PiP button in IINA (a far more capable video player than QuickTime) covers the basics without any third-party install.
