Android Tenant Billing App

I need an Android-only application that lets my staff record each tenant’s electricity consumption and instantly produce a PDF bill at our pre-set rate. How it should work • Staff open the app, choose or enter the tenant ID, type in the current meter reading number and the reading date... (Budget: ₹1500 - ₹12500 INR, Jobs: Android, Android App Development, Android Studio, C# Programming, Data Backup, Database Management, Mobile App Development, Software Architecture)