How to Make a Vesper
Vesper is opinionated software. Every interaction, pixel, and line of code was carefully considered, and no work was too precious to throw away. I’d like to share some history of how Vesper came to look and feel the way it does. - Dave Wiskus
Smart move, writing about the design choices and the great experience. For those who are already using the app, it's nice to see where it al came from. For those like me who didn't buy it yet, it's a clear reason for buying it.
I've just downloaded the app myself and it feels and looks great. People wondered whither it's based on iOS7, and although it's not, it shares a lot of it's principles. Only difference, this one is actually finished and out of beta.