stanleyugwu/easy-vtu ? reverse-engineered prompt

Build me a clean mobile app for the Easy VTU top up platform, something that makes buying airtime, data, and daily subscriptions feel simple and fast.

I want the app to feel modern and easy to use, with a welcoming home screen, clear navigation, and all the main actions easy to find. It should let a user sign in, view their balance, buy top ups, and manage the basics without confusion. Add reusable screens and components so the app feels consistent throughout, and make it work well on Android and iPhone. Use the existing Expo setup and make sure the app runs smoothly from the main entry screen. If you need to check current docs or best practices, go ahead and look them up online.