Just throwing opinions.
App is a super gameplay enhancer for existing players. Playing the game I like and know on a mobile app is a great experience.
But I don't think it's new user friendly and will lead to a new player boom.
I think the idea behind the existence of the app is more being a gameplay enhancer for existing players than being something that will grow a new player boom outside the desktop world. The idea is to have an app and thus make it easier for players to play without depending on a desktop solely. Depending on a desktop nowadays makes it very hard to keep the user base.
Myself I've been away from home and work the last 4 weeks depending basically on the app and things have been fine, way easier than if I had to open the browser on my phone everytime I wanted to do something on BB. Sure, there are some features missing and the experience is not complete yet, but maybe without the app I would have skipped some matches and some important stuff and this would decrease my will for keep playing. Dunno, but I love having the option of using the app.