Today on its blog GoodNotes shared that the upcoming macOS version of GoodNotes 5 would be based on the iPad app using Catalyst:

Earlier this year, we launched our all-new iOS app GoodNotes 5. It has been rewritten from scratch with a much more stable and flexible internal architecture, paving the way for the future of GoodNotes. Rewriting the iOS app also meant that we had to rewrite the MacOS companion because the new GoodNotes 5 was no longer compatible with the outdated existing Mac app. A lot of people were disappointed that we didn’t launch a Mac app together with the iOS version because they still had to stick with GoodNotes 4 if a Mac version was crucial to their workflow. Thanks to the hard work of our Mac team, we released an early-access version shortly after the iOS launch. This beta version is available for everyone who signs up for access. We shipped updates with new features and improvements on a regular basis and were almost ready to launch it publicly when Apple officially announced the start of “Project Catalyst” during their annual developer’s conference in June. It’s a framework that allows developers to bring their iPad apps to the Mac, with a relatively low effort. It still requires a lot of work to create a great Mac app but at least developers don’t have to rewrite significant portions of the code, as it was the case previously.

We believe that it is a great opportunity for us to unify the GoodNotes experience between iOS, iPadOS, and MacOS and will launch the new GoodNotes for Mac using Apple’s new framework.

GoodNotes is a noteworthy Catalyst app not just because it’s a very popular iPad app, but because it already has an existing Mac app. Catalyst makes the most sense for iPad apps that don’t currently have Mac counterparts, but GoodNotes’ plans demonstrate the advantages offered to other apps too. By adopting Catalyst and moving toward a more unified codebase, GoodNotes ensure that users on the Mac will never be left behind again, because new features can be developed and shipped on both iOS and macOS with little added effort.

Our John Voorhees, in his recent Catalyst story, listed GoodNotes as an example of a Mac app that’s fallen behind its iOS version feature-wise, so it’s great to find out that will change in the near future. The only real drawback, as noted in GoodNotes’ post, is that Catalyst apps will require macOS Catalina to run, so users on older versions of macOS won’t be able to download the new GoodNotes 5 for Mac.

Samuel Axon spoke to developers and marketing, developer relations, and engineering representatives from Apple in a story for Ars Technica about Catalyst, Apple’s project for bringing iPad apps to the Mac.

Prior to WWDC, Apple gave a handful of companies access to Catalyst. Axon spoke to three of them about their experiences so far. Nolan O’Brian of Twitter, which discontinued its Mac app in 2016, had this to say about the experience:

“What Project Catalyst specifically offers is the ability to use our existing codebase, meaning that we don’t have to maintain separate code or a separate team to support Twitter for Mac,” he went on to say.

O’Brien said it was relatively easy to get going with the new app: “The surprising thing that got us excited about Project Catalyst was how much of our existing iOS codebase was able to just work.”

TripIt and Gameloft had similar experiences bringing their apps to the Mac.

Addressing the concern that Catalyst means the end of powerful AppKit-based apps on the Mac, Shaan Pruden, Apple’s senior director of partner management and developer relations, explained that there’s a place for ground-up AppKit apps as well as Catalyst apps:

“Good developers will know their audience and their users and what they’re going to want,” she said. “This just opens the door for lots of people to consider coming that wouldn’t have even thought about it before. And I think that’s more the target for this particular technology as opposed to someone who has a very complicated, big, heavy-lifting kind of creative app.”

Todd Benjamin, Apple’s senior director of marketing for macOS, elaborated saying that he:

…believes there are fundamentally multiple types of apps, and they’re not mutually exclusive with one another on a platform. And this is key to understanding Apple’s approach, here. He said:

I think apps on the Mac have always been these large and complex and highly capable apps that are very broad. And I think apps on iOS by nature are a little bit more focused. They’re highly designed. They’re very much considered in what they do and how they do it. And I think that’s changed how people look at apps, right?

The full story, which is full of detailed developer and Apple insights about Catalyst, is worth a read especially since it demonstrates just how nuanced the issues surrounding Catalyst are.