CryptoApp

A modern Android application for tracking cryptocurrency data, built using the latest development standards, Clean Architecture, and Jetpack Compose.

Overview

CryptoApp provides users with a comprehensive list of cryptocurrencies and detailed information about each coin, including market statistics, team information, and price trends. The project demonstrates the implementation of a scalable architecture and efficient data handling in a production-like environment.

Features

• Cryptocurrency List: Browse a list of cryptocurrencies fetched from the CoinPaprika API.
• Detailed Coin Information:
  • Project description and activity status.
  • Tag-based categorization using FlowRow layouts.
  • Comprehensive price change analysis for multiple periods: 24h, 7d, 30d, and 1 year.
  • Listing of project team members.
• Robust State Management: Handling of Loading, Success, and Error states across the UI.
• Data Transformation: Implementation of DTO-to-Domain mapping and data aggregation (combining coin metadata with ticker price data).

Technical Stack

• Language: Kotlin (2.0.21)
• UI Framework: Jetpack Compose with Material 3
• Architecture: Clean Architecture with MVVM (Model-View-ViewModel)
• Dependency Injection: Hilt (2.52)
• Networking: Retrofit 2.9.0 & GSON
• Asynchronous Programming: Kotlin Coroutines & Flow
• Navigation: Jetpack Compose Navigation
• Build System: Gradle with Version Catalog (libs.versions.toml)

Architecture

The project follows Clean Architecture principles by separating the code into three distinct layers:

1. Data Layer: Contains API definitions (CoinPaprikaApi), DTO models, and the repository implementation (CoinRepositoryImpl). It handles data fetching and transformation.
2. Domain Layer: The core of the application. It contains the business models (Coin, CoinDetail), repository interfaces, and Use Cases (GetCoinUseCase, GetCoinsUseCase) that encapsulate specific business logic.
3. Presentation Layer: Responsible for the UI. It uses ViewModels to manage state and Compose screens (CoinListScreen, CoinDetailScreen) to render the data.

API Integration

The application integrates with the CoinPaprika API. To provide a rich user experience, the CoinRepositoryImpl aggregates data from two separate endpoints:

• GET /v1/coins: To retrieve the general list of coins.
• GET /v1/coins/{coinId}: To retrieve specific metadata and team info.
• GET /v1/tickers/{coinId}: To retrieve real-time price changes and market values.

Project Structure

com.bober.cryptoapp
├── common                # Constants, Resource wrapper, and Utility functions
├── data
│   ├── remote            # API interface and DTOs
│   └── repository        # Repository implementation
├── di                    # Hilt modules
├── domain
│   ├── model             # Domain models
│   ├── repository        # Repository interfaces
│   └── use_case          # Business logic cases
└── presentation
    ├── coin_detail       # ViewModels, States, and Detail Screen components
    ├── coin_list         # ViewModels, States, and List Screen components
    └── ui.theme          # Material3 theme definitions