Apple debuts macOS Catalina, which includes the ability to use an iPad as an external display, and will let devs target iPad apps at Mac via Project Catalyst
The next version of macOS will be called Catalina. Apple officially unveiled the new update onstage at its Worldwide Developers Conference (WWDC) today.
Context & Ripple Effects
The WWDC reveal confirms what leaked two months earlier: a desktop-extension feature for macOS 10.15 that sends any window to an iPad, now shipping as Sidecar. The bigger bet is Project Catalyst, which opens the Mac to iPad apps — early beta impressions framed it as the start of a cross-platform era, and by July developers from Twitter, Gameloft, and TripIt were already building on it.
First-order effects
- Developers gain a supported path to bring iPad apps to the Mac, with Twitter, Gameloft, and TripIt among the first through the door on Catalyst.
- Mac users with a compatible iPad get Sidecar, turning the tablet into a second display without third-party utilities like Duet.
Second-order effects
- Catalina also breaks iTunes into Music, TV, and Podcasts, forcing accessory makers and workflow-dependent users to retool around the new app split.
- The Verge's October review finds Catalyst ports lacking next to native Mac apps, pressuring Apple to keep refining the toolchain before developers treat the Mac as a first-class target.
Third-order effects
- If the pattern holds, the iPad-Mac boundary keeps dissolving at the OS level — a trajectory that runs from Sidecar to Monterey's Universal Control, where one trackpad moves between both devices.
- A shared app layer across iPad and Mac shifts Apple's platform economics toward a single developer audience, weakening the case for maintaining fully separate software ecosystems.
The trend: Apple is converging iPad and macOS into one continuous computing surface, using shared apps and hardware continuity rather than merging the operating systems outright.