Don't feel bad about it, if you did. I launched a combo macOS/iOS app last year and wrote (yet-another...) framework to bridge the gap between AppKit/UIKit. Th

Don't feel bad about it, if you did. I launched a combo macOS/iOS app last year and wrote (yet-another...) framework to bridge the gap between AppKit/UIKit. There's an insane number of minute differences, even with Apple trying to make it better behind the scenes (e.g, NSCollectionView _can_ have a similar API to UICollectionView, but it's really not the same beast - it's much easier to tank performance on it). Apple has, IMO, hands down the best UI framework(s) outside the web platform, and they're outright crippling them by what they're doing here. The AppKit community also needs to do their part and not be so resistive to modernizing how it's all learned. tl;dr it sucks.