The idea is to give aspiring app developers a dead simple "vanilla" swift library to start with. Just add some end point calls to instagram and you could literally have a minimal insta client in a day.
I wanted to make a very responsive fluid app like instagram or snapchat. But using apples own app framework always ended up feeling kind of outdated and slow. The concept is really simple. It's just 1 horizontal UICollection and 1 vertical UICollection. The current version uses only 1 RootViewController. The CollectionViews are UIViews with delegate handlers. This makes it really easy to transition to another ViewController. And it also enables you to embed FlowLayout in pure UIView setups like an image picker or alike.