I am eagerly awaiting an app for both iOS and android. What I have seen so far is nowhere near as good as your proposal.

I've noticed on my phone (still rocking the 4s I know time for an upgrade) that when there are a lot of comments the scrolling feature gets somewhat "jumpy" for a lack of a better term. That may be due to the processor of my ancient phone, but would be interested to have others weigh in.

Being able to post content from a mobile device easily will be key. Maybe you could work with @blueorgy to integrate the Steemimg.com file hosting service into the app.

It is very difficult to format with raw html on the phone, so an easy "Microsoft Word" type editor would be useful.

Push notifications are a must as you noted already, and whether steemit chat it the best for mobile or if you wanted to come up with something more similar to fb chat that would be a pretty nice edition.

Maybe instead of clicking on the little reply button when you go to make a comment something like this would be helpful.

So if you clicked anywhere inside one of those rectangles (the rectangles are just for reference) it would open a reply text box.

Also to the best of my knowledge the little // inside the square at the bottom right of the text boxes for comments and posting blog posts does not allow you to drag and make it larger so you do not have to scroll up and down to edit comments.

But I'm excited to see this come to fruition. If I can be of any help to you @sirwinchester, please feel free to contact me. Whether that be ideas or features etc. Would love to be a part of this project.