Aperture is a professional photo editing software. In its days of fame, it competed with big names like Adobe Lightroom. Aperture’s current version originates in 2010. Mac computers are often chosen by photographers, artists, musicians and movie creators, so it was a surprise when Apple decided to discontinue Aperture back in 2014, which was very popular between photographers. Though it was not updated since then, Aperture continued to work, but it was just a question of the time, when Aperture will be bricked. And that time came. Aperture no longer works on macOS Catalina.
Aperture 3 is a 64-bit application, so dropping support for 32-bit apps is not an issue. macOS Catalina bricked many apps, including Aperture 3. Apple offers official document, where you can learn how to migrate Aperture 3 libraries into Photos app, or even Lightroom Classic from Adobe.
Apple created app called “Photos”, but in time of introduction, it was just a toy in compare to Aperture 3. After some time, it got many features from Aperture and you can event install plugins to extend its feature set. I’m personally using Luminar and Aurora HDR from Skylum software, which have great Photos app extensions – right in Photos app, you can enjoy all features from these editors. If you have installed Affinity Photo, definitely check Photos app, because Affinity Photo offers some great plugins too.
I was afraid about future of Final Cut Pro X after I read that Aperture 3 will be discontinued and replaced by (in that time) toy app. It was looking like Apple is abandoning professional market. But Final Cut Pro X is still updated and in active development. It got full support for macOS Catalina and support for XDR displays and 28-cores CPU introduced with brand-new modular Mac Pro.