I want to move my small-scale bookkeeping from spreadsheets into a dedicated Android application that lives only on my phone. The core workflow is straightforward: record every sale or purchase once, then let the app keep me up to date on who owes me, what I owe, current stock levels, asset value, expenses, and a running profit and loss statement. Platform The build is Android-only, so please target current OS versions using native tools such as Android Studio with Java or Kotlin. An offline first design with a local SQLite or Room database is fine; I do not need a cloud backend. Interface A simple, minimalistic UI is essential. Clean screens, clear typography, no flashy colours. Think quick entry forms, concise tables, and a dashboard that surfaces key numbers at a glance. Security On first launch the user sets a password; every subsequent session starts with that password gate. No biometric login is required. All data should stay on the device and be encrypted or at least stored in private app storage. Core features • Debtors and creditors ledger with running balances • Stock or inventory module that updates automatically after each sale or purchase • Asset register that stores acquisition cost, date, and optional notes • Expense entry with category tagging • Automatic profit and loss calculation based on the above inputs, shown in a daily, monthly, and year-to-date view Deliverables and acceptance • Signed APK ready for direct installation on Android 10 and above • Full, well-commented source code I can open in Android Studio • Brief read-me describing database schema and how figures are calculated • Functionality verified by me: password protection works, all five data areas store and retrieve correctly, P&L totals match sample figures I will provide Keep the build lightweight, reliable, and easy for me to maintain or extend later.