<p>Specifically, I am looking to use CA on properties of types other than </p>

<ul>
<li>integers and doubles</li>
<li>CGRect, CGPoint, CGSize, and CGAffineTransform structures</li>
<li>CATransform3D data structures</li>
<li>CGColor and CGImage references</li>
</ul>

<p>and in objects other than CALayers or NSViews</p>

Well, it seems I cannot do that. What I should be doing is [subclassing NSAnimation](
https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/AnimationGuide/Articles/TimingAnimations.html
subclassing NSAnimation). This will work on a MacOS 10.4+ app, but not on Cocoa Touch, in which I cannot find any alternatives apart from using a NSTimer.