I recently made a post about what needs to change on Steemit as it grows, and I honestly think any of the stuff mentioned in the post would serve as a good point for zappl features. Best thing I can suggest though for Zappl is a live streaming service. Stemq is coming soon so youtube is covered, you've already mentioned a twitter service. All that is missing is a twitch counter part here on steemit, which could be the new livesteaming service on zappl. Let me know what you think and maybe check out my post.

https://steemit.com/steemit/@trismegistuz/what-does-steemit-need-to-improve-going-forward
@zappl @zappl-features