Have you been chipping away at this since 2014 or did something change in your motivation recently where you decided to complete it?
What would your reaction be to someone suggesting a rewrite in Electron so you could achieve crossplatform support?
These might seem like minor things, and they probably are for most people, but as an heavy iOS user I have a very good sense for how system components look and function, and it drives me up a wall when people reimplement them but break or fail to support some of their behaviors (specifically: if your custom component is supposed to look like a system control, it better act exactly like one!). As an iOS engineer I also know that these parts of UIKit are the somewhat problematic to deal with, but I appreciate apps that take the time to get it right and I would have hoped that an app that prides itself on looking at home on iOS would have put in the effort to care about this as I do. Hope this helps.
Electron wouldn't be a great idea since it doesn't work on iOS. React Native would be something to consider, but I've never been super impressed by any of the results (and it comes with a bunch of issues in and of itself, and to my knowledge isn't compatible with macOS like UIKit is now) so I'd change nothing in that regard.
Out of curiosity, when did you work at Apple? Your website says "built by a former Apple employee", but it seems you've been full-time on this app for most of your post-college years.
Great app though, I use it :)
https://www.reddit.com/r/IAmA/comments/cfnfu8/my_names_chris...