Banglerun with a custom mobile app

I'm trying to do that, but i don't understand how this can fix the way app.js appers. I've nevere used before rollup, i'm reading now the documentation, but running

rollup -c

gave me errors.
Otherwise, running rollup app.js it seems like is rollup to generate app.js in that way.
Maybe i misunderstood what you said, but i keep trying to fix this, if i solve, will publish the code of corrected file in this conversation.

Thank's you @Gordon.