Developer needed to improve progressive web app

I have a trivia-style web app that needs various changes in game logic, backend analytics, and overall UI/UX & graphic design. I want someone who has experience developing mobile-friendly web apps and is able to work within the backend framework already in place so I don't have to start from scratch. The site was built using React Native framework and is currently hosted on Firebase. For those who are genuinely interested in helping build out this project and expanding on my vision long-term, I'm potentially willing to offer equity (depending on performance). Otherwise, I'm happy to negotiate a fair hourly wage outside of the range posted.