Modernize Minimalist UX/UI for Production App

I need a UX/UI expert to enhance the design of my small app (5-7 screens) currently in production. The goal is to upgrade its look to a sleek, modern and minimalist style while also improving its navigation flow.
The ideal candidate should have experience in:
- UX/UI design, specifically for mobile applications
- Incorporating new visual assets into an existing app
- Enhancing navigation flow
- Implementing a modern and minimalist design aesthetic

I will need new icons and images to be integrated into the updated design. Please provide examples of your previous work that align with this project.