K-Chat

A real-time messaging Android application built with Kotlin, Jetpack Compose, Room Database (for offline caching), Firebase Firestore (for real-time data sync) and Cloudinary (for cloud storage of media & statuses).

Installation

Phone Prerequisites

• Android OS: Android 7.0 (Nougat, API Level 24) or higher.
• Google Play Services: Required for Firebase services.
• Permissions: Internet access (for sync) and notification access (optional, to show incoming message alerts).

Install via APK

1. Download the K-Chat APK (or visit the GitHub Releases page) directly on your Android device.
2. If prompted, enable installation from unknown sources in your device settings (Settings > Security or Settings > Apps > Special app access > Install unknown apps).
3. Open your device's file manager, navigate to the Downloads folder, and tap on the downloaded .apk file.
4. Tap Install and follow the on-screen instructions.

Features

Authentication

• Phone-Based Authentication: Login with OTP verification.
• Session Persistence: Auto-login capabilities using DataStore Preferences.

Messaging

• Real-Time Text Chats: Fast, responsive messaging using real-time Firebase Firestore synchronization.
• Image Sharing: Send and receive photos securely, with upload integration to Cloudinary.
• Image Viewer: Full-screen interactive viewer for high-quality media messages.
• Message Status:
  • SENT: Message uploaded to the server.
  • DELIVERED: Updated instantly when the recipient is online using GlobalDeliveryScanner.
  • READ: Marked when the recipient opens the chat.
• Message Controls:
  • Delete for Me: Removes the message locally and marks it in Firestore.
  • Delete for Everyone: Replaces the message content with a tombstone (🚫 This message was deleted) for all chat participants.

Live Status / Updates (Stories)

• Text Status: Write text updates with dynamic background colors.
• Photo Status: Upload status images directly via Cloudinary.
• 24-Hour Expiration: Automatic status deletion and clean-up of stale updates.

Notifications & Presence

• Push Notifications: Live messages delivered via Firebase Cloud Messaging (FCM).
• Deep Linking: Seamless routing directly from notifications to specific chat screens using custom URI schemes.
• User Presence: Dynamic online/offline status indicator displayed in real-time.

Architecture & Tech Stack

The app is built using Jetpack Compose for a fully declarative and modern UI.

• UI Framework: Jetpack Compose
• Local Cache: Room Database for caching messages locally, facilitating fast load times and offline support.
• Database Backend: Firebase Firestore for instant remote sync.
• Image Loader: Coil for asynchronous Compose image loading.
• Cloud Storage: Cloudinary SDK for media storage.
• Dependency Management: Gradle Version Catalog (libs.versions.toml).
• Asynchronous Flow: Kotlin Coroutines & Flow.