Tiyin

A modern Android subscription tracker built with Jetpack Compose, Firebase, and Clean Architecture. Track all your recurring subscriptions, monitor costs, and never miss a payment.

---

📸 Screenshots

Dark — Home	Dark — Details	Dark — Settings	Light — Home

---

Why Tiyin exists

Managing subscriptions is annoying in real life. People use multiple services like Netflix, Spotify, and others, and over time it becomes hard to track how much money is actually being spent every month.

Sometimes subscriptions renew without notice, and users only realize it after money is already gone. From my experience, most people don’t track this properly and just accept the loss.

Tiyin was created to solve this problem in a simple way. The goal is to give users a clear view of all their subscriptions, show the real total cost, and help avoid unexpected payments.

---

Features

• Subscription management — Add, edit, and delete subscriptions with service auto-recognition
• Multi-currency support — Total cost calculated and converted to your preferred currency
• Sort & filter — Sort by expiry date, cost, or name
• Progress tracking — Visual progress bar showing time elapsed in the current billing cycle
• Auto-renewal detection — Subscriptions auto-roll when a period expires
• Payment reminders — Get notified before upcoming renewals
• Cloud sync — Subscriptions backed up and synced via Firestore
• Dark / Light theme — Full Material 3 theming support

---

Architecture

Tiyin follows Clean Architecture with a multi-module Gradle setup, separating concerns across three layers:

app/
├── data/           # Repositories, Firestore, Room, mappers, DI modules
├── domain/         # Models, repository interfaces, use cases
└── feature/
    ├── home/       # HomeScreen, HomeViewModel, HomeUiState, HomeIntent
    ├── analytics/
    ├── settings/
    └── ...
ui/                 # Shared Compose components (SubscriptionCard, ServiceLogo, etc.)
navigation/         # Type-safe navigation destinations (kotlinx.serialization)

Layers

Layer	Responsibility
Domain	Subscription, ServiceInfo, use cases (GetSubscriptionsUseCase, CalculateTotalCostUseCase, …), repository interfaces
Data	FirestoreSubscriptionRepositoryImpl, SubscriptionEntity, mappers, Hilt DataModule / RepositoryModule
Feature	MVI-style: HomeIntent → HomeViewModel → HomeUiState consumed by HomeScreen

State Management (MVI)

Each feature uses a unidirectional data flow:

User action → HomeIntent → HomeViewModel → HomeUiState → HomeScreen (Compose)

HomeUiState is a sealed interface with three states: Loading, Success, and Error.

---

Tech Stack

Category	Library
UI	Jetpack Compose, Material 3
Architecture	ViewModel, StateFlow, Clean Architecture
DI	Hilt
Backend	Firebase Firestore, Firebase Auth
Local DB	Room
Navigation	Navigation Compose (type-safe, kotlinx.serialization)
Async	Kotlin Coroutines & Flow
Images	Coil

---

Getting Started

Prerequisites

• Android Studio Hedgehog or newer
• JDK 17+
• A Firebase project with Firestore and Authentication enabled

Setup

1. Clone the repository

   git clone https://github.com/hashiroii/tiyin.git
   cd tiyin

2. Add Firebase config
   Download google-services.json from your Firebase console and place it in the app/ directory.

3. Build & run
   Open in Android Studio and run on a device or emulator (API 26+).

📄 License

MIT License — see LICENSE for details.