I've been happy with Photomator (now owned by Apple). It's Apple-only, with versions for iOS/iPadOS and Mac. It integrates seamlessly with the Apple photo libr

I've been happy with Photomator (now owned by Apple). It's Apple-only, with versions for iOS/iPadOS and Mac. It integrates seamlessly with the Apple photo library. It's only "gotcha" (which I don't find to be a problem) is it leverages Apple processing where possible (ie the Apple RAW engine). That doesn't bother me, but if you're a pro-level photog and need some special sauce for your RAW workflow, it might not work.