Book companion app design

I'm working on an app and I need someone to work on the UX/Design part of it.

Concept: The app is a companion for readers.  It's based on "book chunks", which are bits of information about an element of the book (a new character, a new place, an update on a character, etc). The idea is that someone can select the book they are reading and go through the "book chunks" while they go through the book. Then, if you need to make a search (for instance you don't remember who some character was), you can perform the search which will be limited to the information up to point in the book you are at (i.e. No spoilers).

Here's a basic mockup I've made to show the idea: https://marvelapp.com/prototype/c377b7j
⚠️Important: The mockup is NOT a reference of the design I'm after, it's just to help communicating the overall idea.

There are a few key user flows, they start when the user wants to read a book.
* Creating: If no one has created the book chunks, they can create one themselves (so instead of just navigating through some chunks, they would create them while they go through the book).
* Reading: If someone has already created the book chunks (and made them public), they can simply go through them while they read
* Collaborating: If the user is going through some book chunks that they have NOT created, they can suggest changes on existing chunks (or adding new chunks). Then the creator of the book chunks can decide to accept or reject the changes.

WHAT I NEED:
* Branding (Logo, colors, typographies, etc)
* User Flow Diagram: Maps out the steps users take to complete actions mentioned above
* Navigation Scheme: Details placement of menus and buttons for easy access.
* Design of key pages (Homepage, the pages of the flows mentioned above and the profile page). Designs must be mobile first, but once approved I also need a responsive adaptation of them for desktop.

TOOLS:
I'm open to whatever tool you use (Sketch, Figma, Adobe XD, etc). At a minimum I need the image files, but if you use a tool that would give some extra info (like padding, margins, etc) that's even better.

TIMEFRAME:
This is a side project so I'm not in a rush, I'm open to hear your proposed timeline.


THANKS!