React Native App Update - I need a developer skilled in React Native for this job. You'll update my almost complete app in two ways:- Add a username feature for users on the platform. This should be well structured to display users in order of the amount

This app is near completion, i have attached an example. I have the full code repository and only need updates.

I want the ability to add usernames and have users be listed on a page based in order of the amount of time they have spent. like a ranking.

I will require assistance completing in app purchase that is required to save progress in the app. Only one in app purchase.

The project is written in react native and I will need to see a working version on Expo Go.

Project Overview: The Ascent

Simplicity is key, this is essentially a one page app. Endless runner style sprites coming across the screen. I have all illustrations and layers already made. Below is a link to the almost complete app.

OVERVIEW: The Ascent is a minimalist, high-performance mobile focus app designed for iOS and Android. It translates the ancient Greek myth of Sisyphus into a powerful, game-like psychological anchor for daily productivity.

1. The Core Experience
Upon starting a session, users select their focus duration (e.g., 25, 45, or 60 minutes). The app transitions to a clean, distraction-free screen where Sisyphus endlessly pushes a low-poly crimson boulder up a steep 33° slope. Background layers (terracotta mountains and shifting clouds) scroll past to create a sense of scale, while a precise, real-time HUD tracks their climbing lifetime elevation progress down to five decimal places (e.g., 0.12450 MI).

https://the-ascent.expo.app/