BILLZ - Bill, Budget & Ledger App (React Nativ

BILLZ is a complete, production-tested bill and budget app - the mobile app, the API behind it, and the admin portal. It is not a UI kit or a mockup: this is the same codebase that runs live on Google Play, cleaned up and documented for you.

Most bill-tracker templates stop at the screens. This one ships the whole product. There is a real FastAPI + MongoDB backend with JWT authentication and owner-scoped data, an admin portal for managing users and subscriptions, server-side aggregations so money figures cannot drift between screens, and a monetisation path already wired end to end.

What makes it different from the other trackers available here:

- It answers a question the others do not. Payday Runway forecasts whether your   money actually lasts until payday, names the day you run short, and warns you   before it happens. - It reads real bank statements. Import CSV, QIF, OFX or PDF (including scanned   PDFs) and it detects recurring charges by proving a cadence, then lets the user   confirm. Re-importing the same file is safe - duplicate rows are recognised and   skipped, never doubled. - It has no bank login, by design. The user enters bills or imports a statement,   which removes the whole category of aggregator credential problems. - The reminders are real reminders. An optional exact-alarm native module with a   settings toggle lets alarms fire on the minute instead of "sometime within the   hour", and the app explains Android's special access rather than failing   silently.

Included in the download:

- app/, src/, constants/, modules/, assets/, shims/ - the Expo / React Native app - backend/ - the FastAPI + MongoDB API, full source - android/ - the native Android project - scripts/, mock/ - helper scripts and sample bank statements for demos and tests - Build configuration: package.json, app.json, eas.json, metro.config.js - BUYER-SETUP.md - step-by-step deployment and rebrand guide - DOCUMENTATION.md and Buyer-Documentation.pdf - the full manual - PACKAGE-MANIFEST.txt - exactly what is included and what is not

The app is Android-first and live on Google Play. The shared React Native code is cross-platform; shipping iOS needs your own Apple account and an iOS build.

Features

- Bills - payable and receivable, with amount, due date, category and notes - Recurring bills - weekly, monthly, yearly and every-N-days, with automatic   advance to the next due date when an occurrence is marked paid - Auto-pay flag for bills that leave the account on their own - Reminders - on/off, time of day, and how many days ahead - Optional exact-alarm native module, with a Settings row for Android's   special-access toggle so reminders are not delivered up to an hour late - Payday Runway - forecasts every bill between today and payday, names the   shortfall date and sends an alert two days ahead (free: one payday, Pro: four) - Ledger - one-off income and expenses, filter chips, windowed totals, bulk delete - Bank statement import - CSV, QIF, OFX, PDF text layer, and OCR for scanned PDFs - Automatic recurring-charge detection from imported statements, added as bills   in one tap - Duplicate-safe re-import - identical rows are recognised and skipped - Accounts - checking, savings, cash, investment, credit card and loan types - Net worth with a real assets-versus-liabilities split, and a per-account   include/exclude toggle - Per-account spending activity plus an "unassigned rows" warning card - Budgets per category, with ledger spending counted against them - Savings goals with progress - Debt payoff planner that ranks debts for the fastest payoff - Reports - selectable windows (this month / last month / 3 months / all time),   period comparison, and spend by account - Charts tab - Calendar view of what is due each day, month by month - AI Spending Insights - LLM-written summaries with a multi-provider fallback   chain (OpenRouter/DeepSeek, then Google Vertex AI Gemini, then DeepSeek direct)   and a health endpoint - Subscriptions and free-trial tracking, including the cost once a trial ends - Household sharing for shared bills - Document vault for receipts, warranties and documents - Email digest - Backups, restore and CSV export - App lock via device biometrics - Pro tier via a one-time Google Play purchase, verified server-side with the   Android Publisher API, with purchase restore - AdMob banner and rewarded ads on the free tier - Admin portal - user management, overview, payments, ban/unban, Pro grant and   revoke, refunds, audit log, feedback, and the app-version release gate - App-version gate served by the backend, with an in-app check for updates - Full EAS build and OTA update configuration

Requirements

Technical requirements

- Node.js 20 or newer, with npm - Expo / EAS CLI - JDK 17 and the Android SDK, for native builds - Python 3.12 for the backend - A MongoDB database (a hosted free tier is enough, or your own server) - A Google Play developer account, to publish - A container host if you deploy the backend elsewhere - a Dockerfile is included   in backend/

Stack

- Frontend: Expo SDK 54, React Native 0.81, React 19, Expo Router 6, TypeScript - UI and charts: react-native-gifted-charts, react-native-svg, Reanimated 4,   Gesture Handler, Keyboard Controller - Backend: FastAPI (Python 3.12), Uvicorn, MongoDB via the async motor driver,   JWT (PyJWT) with bcrypt (passlib) - Statement parsing: pypdf, pandas, custom CSV / QIF / OFX parsers, and OCR for   scanned PDFs - Payments: Google Play Billing (react-native-iap), verified server-side with the   Android Publisher API - Ads: Google AdMob (react-native-google-mobile-ads) - Android only, shimmed on web - AI: OpenRouter / DeepSeek, with Google Vertex AI Gemini as a fallback - Email: Gmail SMTP - Reminders: expo-notifications plus a custom Kotlin exact-alarm module - Native: custom local Expo modules written in Kotlin (exact alarms, widget bridge) - Build and release: EAS Build and EAS Update (OTA), Gradle, Kotlin 2.2.20,   Android target SDK 35

Accounts and keys you must supply

- Your own Firebase project and google-services.json - Your own Google Play service-account JSON for in-app purchase verification,   plus the Play Console permission grant - Your own AdMob application ID and banner / rewarded unit IDs - Your own signing keystore - Your own MongoDB connection string - A Google Cloud project if you want the Vertex AI fallback for insights

The original author's accounts, API keys, signing keystore and Play service account are deliberately NOT included, so nothing in the package points at someone else's accounts.

Skill level

You should be comfortable running an Expo / React Native project and deploying a Python API to a container host. This is real full-stack source, not a no-code builder export and not a single-screen UI kit.

Instructions

Getting it running

1. Read BUYER-SETUP.md in the download - it walks through the backend, the app    and the rebrand in order. 2. Deploy the backend folder to your host and fill in the values listed in    backend/.env.template. 3. Check that GET /api/healthz and GET /api/app/version respond before going    further. 4. Point src/lib/backend-url.ts at your backend URL, then npm install and build    with EAS. 5. Rebrand: app.json (name, slug, scheme, package id), the icons and splash in    assets/images/, and your AdMob IDs.

Using the app

Bills and reminders 1. Tap the round + on the dashboard or the Bills tab. 2. Enter the name, the amount and the due date, and choose Payable (money you    owe) or Receivable (money owed to you). 3. Pick a repeat option for anything monthly or weekly. Mark an occurrence paid    and the app records it and advances to the next due date. 4. Settings -> Notifications turns reminders on and sets the time of day and how    many days ahead. On Android 12+ also open Settings -> Preferences and grant    the exact-alarm access, or a reminder can arrive up to an hour late.

Payday Runway 1. Tap the Payday Runway card at the top of the dashboard. 2. Enter your next payday, the amount and optionally what you have now. 3. It forecasts every bill up to payday and warns you before you run short. 4. The card stays hidden while there are no bills, because there is nothing to    forecast yet.

Ledger and statement import 1. Tools -> Import a statement, then choose a PDF, CSV, QIF or OFX file, or scan    a paper bill with the camera. 2. Review what it found, and add any detected recurring charges as bills in one    tap. Re-importing the same file is safe - duplicates are skipped. 3. Tools -> Ledger for one-off rows. The filter chips change the totals, and the    line above the list names the window it counted.

Accounts, budgets, goals and debt 1. Money -> Accounts, add an account and pick its type. Credit card and loan    count as money you owe and lower net worth; checking, savings, cash and    investment count as assets. 2. Move imported ledger rows into an account - the warning card tells you how    many are still unassigned. 3. Money -> Budgets, Goals and Debt for the monthly plan, savings targets and the    fastest-payoff debt order.

Reports, calendar and insights 1. Money -> Reports, pick a window, then compare periods or view spend per    account. 2. The Calendar tab lays bills out on the days they are due; tap a day to see it. 3. Tap the AI Insights card on the dashboard to read the generated summary.

Everything else 1. Tools -> More tools for subscriptions and free trials, household sharing, the    document vault and the email digest. 2. Settings -> Data backs up, restores, or exports CSV. 3. The in-app Guide, reachable from the dashboard header, the Tools tab, Settings    and About, explains every feature - in the same order as DOCUMENTATION.md.

Pro 1. A one-time purchase through Google Play - never a subscription. 2. It unlocks unlimited bills (free stops at 7), all charts, unlimited AI    insights, a four-payday Runway forecast and the Ledger's bulk delete. 3. On a new device, open any upgrade screen and tap Restore purchases.