I want to release a lean MVP that works like Khata Book on Android. The focus is a clean ledger for micro-business owners, not a full-blown accounting suite, so keep the build tight and efficient. Scope of this first build • Expense tracking – add, edit, and delete debit/credit entries with running balance per customer. • Customer management – create customer profiles and list their individual ledgers. • Phone number / OTP authentication – simple, reliable sign-in flow (Firebase Auth or a lightweight alternative). What I’m expecting – Modern Android code (Kotlin or Java) in Android Studio. – Local persistence that can later be switched to cloud; SQLite or Room is fine for now. – Clear, modular architecture so future reports or analytics screens can be plugged in later. – Source code, build instructions, and an APK for testing. If you already have a starter template or have built something similar, let me know—speed and code clarity matter.