Ledger.AI

Local-first, privacy-centric financial intelligence for mobile

Ledger.AI transforms raw mobile notifications (SMS, push, UPI) into a structured, searchable financial ledger — without cloud APIs, bank logins, or OAuth intermediaries.

Core Premise

• Every financial transaction generates a notification
• These notifications contain all the data we need (merchant, amount, category)
• By intercepting at the OS layer, we bypass API complexity entirely
• On-device LLM (Gemma 4) parses unstructured text into structured records
• Financial data never leaves the device

Current Status

Phase: Foundation (Phase 1) — Core infrastructure complete

Component	Status
Project scaffolding	✅ Expo SDK 55, TypeScript strict, ESLint, Prettier
SQLite database	✅ op-sqlite with WAL mode, migrations, repositories
Basic UI	✅ Navigation, tab structure, transaction cards
SMS reader module	✅ Custom Expo module for inbox query
Notification listener	✅ Manifest-registered BroadcastReceiver (pending device test)
Transaction list	✅ FlatList with date grouping, empty states
Manual entry	✅ Form for testing/fallback
LLM integration	✅ Classification + parsing (PoC validated)

Key Features

🔔 Real-time SMS Processing

• Manifest-registered BroadcastReceiver captures SMS even when app is killed
• Inbox-as-queue architecture (no data loss on force-quit)
• Capped processing (20 SMS max) to avoid thermal issues

🤖 On-device LLM

• Gemma 4 E2B Q4_K_M (~2GB, fits on 4GB+ devices)
• Classifies SMS → parses to structured JSON → inserts to SQLite
• Falls back to regex parser for low-end devices

📊 Transaction Management

• SQLite with WAL mode, SQLCipher encryption
• Repository pattern for CRUD operations
• Summary strip, date grouping, empty states

Tech Stack

Layer	Technology
Framework	Expo SDK 55+ (with prebuild)
Language	TypeScript (strict)
Database	op-sqlite (JSI-based SQLite)
State	Zustand
Navigation	React Navigation v6
Local LLM	llama.rn + Gemma 4
Notifications	Custom Android NotificationListenerService

Project Structure

├── app/                      # Expo Router screens
├── src/
│   ├── components/           # UI components (cards, empty-state, etc.)
│   ├── database/             # SQLite + repositories
│   ├── parsers/              # LLM + regex parsers
│   └── hooks/                # React hooks
├── modules/
│   ├── sms-reader/           # Expo module for SMS inbox query
│   └── sms-listener/         # Expo module for real-time SMS capture
├── hooks/                    # Global hooks (use-sms-listener.ts)
└── .documentation/            # Plans, evidence, decisions (project memory)

Documentation

This project uses structured documentation in .documentation/:

• PROJECT_PLAN.md — Living roadmap
• plans/PLAN-NNN-* — Feature plans
• evidence/EVIDENCE-NNN-* — Validation results
• decisions/ADR-NNN-* — Architecture decisions

See CONTRIBUTING.md for development workflow.

Quick Start

# Install dependencies
npm install

# Run on Android (requires physical device for SMS features)
npx expo run:android

Build for Device

# Clean prebuild
npx expo prebuild --clean

# Build debug APK
cd android && ./gradlew assembleDebug

# Install and test SMS capture
adb install app/build/outputs/apk/debug/app-debug.apk

Next Steps

1. ✅ Phase 1: Foundation (complete)
2. 🔄 Phase 2: PoC — Device testing of notification listener
3. ⏳ Phase 3: MVP — Auto-categorization, insights, battery optimization
4. ⏳ Phase 4: Polish — iOS support, model fine-tuning, Play Store

Privacy

• No cloud APIs
• No data leaves device
• SQLCipher encryption at rest
• No analytics, no tracking

License

MIT License