Advanced Android Billing App

I’m building a single Android application that handles every step of small-business billing in one place. The core of the project is an all-in-one module that lets me: • generate professional invoices on the phone, • process customer payments in-app, and • track expenses in real time... (Budget: ₹12500 - ₹37500 INR, Jobs: Android, Android App Development, API, API Development, Java, Kotlin, Mobile App Development, Software Architecture)