Paid, polished window snapper for Mac power users

What to build

A polished, paid macOS window-tiling app forked or rebuilt from GridSnap's open-source core, adding custom grid layouts, fully remappable keyboard shortcuts, and per-monitor saved profiles for multi-display setups — sold as a one-time purchase or small subscription to Mac power users and ex-Windows switchers who miss FancyZones.

GridSnap proved there's open demand for Divvy/FancyZones-style tiling on macOS, but as a free community tool it leaves the polish and advanced features (custom layouts, shortcuts, multi-monitor profiles) on the table for a paid competitor to capture.

Demand

Ex-Windows switchers and power users who relied on FancyZones or Divvy want equivalent tiling on macOS now, especially as more multi-monitor remote/hybrid setups make manual window arranging painful; GridSnap's HN traction shows this pain point still gets people to click and comment.

• Hacker NewsEngagement

  GridSnap – an open-source Divvy-style window snapper for macOS — 48 points, 26 comments on HN, indicating high engagement at the source.

• GridSnap GitHub repositoryProduct

  Open-source Divvy-style window snapper for macOS; its existence and HN discussion signal unmet demand for more polished custom layouts, shortcut customization, and multi-monitor profile support.

• Historical precedent: Divvy and FancyZonesMarket

  Divvy (paid, macOS) and FancyZones (free, Windows PowerToys) both built real user bases around grid-based window tiling, and ex-Windows switchers frequently cite missing FancyZones-equivalent functionality on macOS as a pain point.

Stack

• Swift + AppKit (Accessibility API for window control)
• Sparkle (auto-updates for direct-sale distribution)
• Carbon/Cocoa global hotkey APIs (HotKey library)
• Mac App Store Connect + StoreKit (or Gumroad/Paddle for direct sales)
• SQLite or plist for layout/profile persistence

Solo + AI difficulty

The core mechanics (window resizing via Accessibility API, hotkey binding, grid math) are well-trodden and AI can scaffold most of it quickly since GridSnap's code is a working reference; the hard parts are macOS permission UX (Accessibility/Screen Recording prompts), multi-monitor edge cases, and polishing enough to justify charging money against free alternatives — realistic time-to-MVP is 2-4 weeks for a solo builder already comfortable with Swift/AppKit.

Entry threshold

Low barrier: window management on macOS is well-documented via Accessibility APIs, a solo developer can ship a Swift/SwiftUI app in 1-2 weeks; main effort is UX polish and notarization/distribution rather than novel engineering.

Window

3-6 months

Where to find first users

• Mac App Store search/browse
• Product Hunt launch
• r/macapps and r/MacOS
• Hacker News Show HN post referencing the original GridSnap thread

Competitors

• Rectangle
• Magnet
• Moom
• Divvy

Counter-signals & risks

• macOS already has multiple established paid competitors (Magnet, Moom, Divvy) and a popular free alternative (Rectangle), making differentiation and customer acquisition difficult for a new entrant.

• Apple's native Stage Manager and ongoing window-tiling improvements in recent macOS versions reduce the addressable pain point over time.

• Because GridSnap is open-source, the community could simply improve it directly or others could fork/rebrand it for free, undermining the value proposition of a paid product.