I am open sourcing my Meteor application written with Mantra. The app is called Vym. The source code is available in this repo.
It is hard to get started using Mantra because:
there are not many practical examples. There are some sample repos but they are expository at best.
there is no official tutorial.
I hope to address the first problem by building an open source application using Mantra.
I think some real life examples like this would have really helped me when I got started. Feel free to ask me questions and I am happy to share the inner workings.