I've been using Vector for Android the last days and I must say I am VERY impressed. Both the vector.im web interface and the smartphone apps are looking polished at a level that I'm very unused to when it comes to open source projects.

I must say though that people are becoming more and more unfamiliar with decentralization. Naming the standard one thing (Matrix) and the main phone app another (Vector) is IMHO a move that only a technologist would come up with. The logic might seem crystal clear to all you working on the project. But if you want traction (hell, you could actually be a serious alternative to Slack!) you should've register something like matrix.im and named the app Matrix.