A great way to show Sketch a possible direction they should aim for (if they're not doing that already). I believe that prototyping should be integrated into the design software, since it's not just about creating "screens" anymore.

I would love to see an extra "preview" option via the browser, to avoid double work in order to share a prototype with clients for feedback/presentation. For now, Invision will do just fine :).

Keep up the cool work!