Kinda, but Square actually had an alternative way of managing UI flow, enabled by a couple libraries they wrote, and a bunch of other support libraries for basic stuff like making HTTP requests, all of which was so much saner than Google's standard way(s) of doing things. You'd end up writing Square/Android, in the sense of GNU/Linux, if that makes sense. Why Square, of all places, straight-up killed it on that particular platform, I have no idea (no shade intended to folks at Square, it's just unexpected situation). It's not like they just had a really good project template or something.