You assume a lot. My sister (who just replied to you) babysat for over a year to save up for a windows product and decided to get the iPad when it came out. I saw the whole process and she genuinely loves it — not because she is a fan girl but because it has made a huge impact on her career. I think it's a super inspiring story for artists young and old and a genuine compliment to the iPad Pro.
Our apps have been featured dozens of times and there is definitely a method to the madness. I shared my 2 cents on how to get featured as a comment on that HN link.
I would add, I think there are two steps to getting featured:
1) Make your app featurable: solves a problem in a well designed, polished way. Bonus points for showcasing one of Apple's new technologies (right now things like 3D Touch or iPad Pro optimization).
2) Get noticed by Apple: if you can make a small splash, Apple may make you a bigger one. Apple are kind of like app journalists: they are scouring the web to find out about upcoming gems or breakaway successes. I'm sure they also look at what new apps are making a splash in the charts. I think they found my first app, Grades, because I wrote a blog exploring how to build successful apps and some folks at Apple read it. You can also meet Apple folks on Twitter, conferences, and especially WWDC.
After consistently releasing apps that Apple is impressed with, they may start to build a more personal relationship with you and that's the goal.
Some people think this is all about luck but, as someone who started as a poor college student no one knew about, I found there is a method to the madness.
It isn't much better for simple animations like this but I find it much easier for complex, gesture-based, dynamic animations that can change at any time based on user input.
Given that much of the Paper prototyping was done in Origami, this was my first thought when I saw this library. I haven't actually used Paper yet (it's still US-only) but I'm in love with these kinds of tactile, fun interfaces.
I think the main difference is they are easy to interrupt and continue from the current real position, where doing that with CA is more difficult. That would let you do some nifty stuff with gestures, I guess.
I'm really sorry for the site errors. It was down for about 2 hours. Never had to deal with so much traffic before and my host shut it down. Should be back up for everyone now.