README.md

Expenso

A shared expense tracker for couples, built with Swift (UIKit) and React Native.

What it does

Expenso lets two people track shared expenses and income in real time. Each transaction records who paid, the category, amount (EUR), and an optional note. A balance card shows the current month's total with a month-over-month comparison.

Features

• Add expenses and income with category, payer, and notes
• Real-time sync via Firebase Firestore
• Monthly balance with percentage change vs previous month
• Swipe-to-delete transactions with animated feedback
• Categorized spending (Supermarket, Coffee, Food, Gym, etc.)

Tech Stack

Layer	Technology
Native shell	Swift, UIKit, Auto Layout
Transaction list	React Native 0.79, TypeScript
Animations	React Native Reanimated 3
Database	Firebase Firestore (real-time listener)
JS Engine	Hermes
Icons	Lucide (RN), SF Symbols (native)
Fonts	DM Sans, Bricolage Grotesque

Project Structure

expenso/
├── ReactNativeModule/          # React Native module
│   └── src/
│       ├── index.js            # Registers TransactionList component
│       ├── TransactionList.tsx  # Transaction list with real-time updates
│       ├── TransactionRow.tsx   # Swipeable row with delete gesture
│       ├── Icon.tsx             # Lucide icon wrapper
│       └── theme.ts            # Shared colors, fonts, spacing
│
├── Expenso/                    # Native iOS Xcode project
│   ├── Expenso/
│   │   ├── AppDelegate.swift           # App entry, Firebase init
│   │   ├── SceneDelegate.swift         # Window scene setup
│   │   ├── MainViewController.swift    # Main screen layout
│   │   ├── AddEntryViewController.swift # Add transaction sheet
│   │   ├── BalanceCardView.swift       # Balance card with month comparison
│   │   ├── FirestoreService.swift      # Firestore CRUD + listener
│   │   ├── RNBridge.swift              # Native → RN event emitter
│   │   ├── TransactionType.swift       # Data models & enums
│   │   ├── CategoryType.swift          # Category definitions
│   │   └── Theme.swift                 # Design tokens
│   ├── Fonts/                  # DM Sans, Bricolage Grotesque
│   ├── Podfile                 # CocoaPods dependencies
│   └── .xcode.env              # Build environment
│
├── package.json                # Root config with codegen settings
└── react-native.config.js     # Links iOS project to RN dependencies

Architecture

Firestore (real-time listener)
    ↓
FirestoreService (Swift)
    ↓
BalanceCardView (native)  +  TransactionBridge (event emitter)
                                     ↓
                             TransactionList (React Native)

The native layer owns data, navigation, and the balance UI. The React Native layer renders the scrollable transaction list, receiving updates via the bridge event emitter.

Setup

Prerequisites

• Xcode 26+
• Node.js 22+
• CocoaPods

Install

# Install RN dependencies
cd ReactNativeModule
npm install

# Install iOS pods
cd ../Expenso
pod install

Build

Open Expenso/Expenso.xcworkspace in Xcode and build to a device or simulator.