Probably very little if it is built on top of CoreAnimation, since that set of OS APIs is extremely heavily optimized specifically to enable animation-rich UIs that are light in terms of CPU and battery use.
Indeed. As far as I know, Core Animation was originally created as part of work on the first version of iOS (née iPhoneOS), where the target device, the original iPhone, was pretty severely memory and CPU constrained.
> [The] advent of Core Animation probably means that we'll have to endure some amount of gratuitously animated software created by "overly enthusiastic" developers. But the same was true during the introduction of styled text and color graphics. Mac developers learn quickly, and Mac users are good at rewarding restraint and punishing excess.
Right, it was introduced publicly as an API in Mac OS X Leopard, but my understanding has always been that it was actually conceived as part of iPhoneOS, then ported to Mac as well. The iPhone shipped a few months before Leopard, though of course UIKit wasn’t made public until the next year when the iPhone SDK was first released.
There’s a similar story around SwiftUI. It was initially created by the Apple Watch team at Apple, then extended to all the other OSes (all this was long before it was made public).
