CoLink • Connect all your devices for seamless collaboration.

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Website • Features • Quick Start • Architecture • Development

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CoLink is a cross-platform device connectivity tool that brings everyday sync, remote access, and device control together through a single connection. Whether devices are on the same LAN or connected over the internet, they can collaborate securely.

Features

• Clipboard Sync — Copy on one device and paste on another. Supports plain text, rich text, and images.
• File Transfer — Send files between devices. Direct LAN transfers have no size limit; cloud relay supports up to 10 MB.
• Text Messages — Send notes and text snippets between devices instantly.
• Remote File Access — Browse the file system of a remote device and transfer files between connected devices.
• Remote Terminal & Device Control — Open an interactive terminal on a connected computer from your phone; depending on peer support, control power state, media playback, and system volume.
• Remote Camera — View live video from cameras on connected devices.
• CastBoard — Turn another device into a live status display: show now-playing information, album art, and synchronized lyrics (NetEase Cloud Music, QQ Music, Sogou Music, and Spotify), and sync CPU, memory, network, and other system metrics from your computer.
• Direct LAN Connection — Devices on the same network discover each other automatically through mDNS and connect directly without going through the cloud.

Remote access and control features depend on the client version, platform capabilities, and granted permissions on both devices.

Platform Support	App	Status
Windows	colink-desktop	✅ Available
macOS	colink-desktop	🚧 Coming soon
Linux	colink-desktop	✅ Available
Android	colink-android	✅ Available
iOS	colink-ios	🚧 Planned

Interface Preview

Device List	Message List	Message Page

CastBoard Demo

https://www.youtube.com/watch?v=w7pMdKMIfjg

Synchronized Lyrics
Now Playing
System Metrics

Quick Start

1. Install a Client

Platform	Download
Windows	Latest Release
Linux	Latest Release
Android	Latest Release

2. Connect

1. Open the client and sign up.
2. Pair devices on the same LAN via the 6-digit pairing code, or connect remotely through the server relay.
3. Start syncing clipboard, sending files and messages, or using remote access, device control, and CastBoard.

Self-hosting (Optional)

You can self-host the CoLink server using Docker. See colink-server for setup instructions.

Architecture

                        ┌─────────────────────┐
                        │   colink-server     │
                        │   (Go / Gin)        │
                        │   REST + WS Relay   │
                        └────────┬────────────┘
                                 │
               HTTPS / WSS       │       HTTPS / WSS
        ┌────────────────────────┼────────────────────────┐
        │                        │                        │
        ▼                        ▼                        ▼
┌───────────────┐      ┌────────────────┐       ┌─────────────────┐
│ colink-desktop│      │ colink-android │       │ colink-frontend │
│ Tauri 2.x     │      │ Kotlin/Compose │       │ Vue 3 Web App   │
│ Win/Mac/Linux │      │ Android        │       │ Account Mgmt    │
└───────┬───────┘      └───────┬────────┘       └─────────────────┘
        │                      │
        │  LAN (mDNS + WS)     │
        └──────────────────────┘

Communication Path	Transport	Purpose
Client ↔ Server	HTTPS + WSS	Authentication, device management, cloud relay
Client ↔ Client (LAN)	mDNS + WebSocket	Direct P2P on the same network
Frontend ↔ Server	HTTPS	Account management

Security

• Each device has its own Ed25519 key pair as a non-forgeable cryptographic identity, with online rotation support.
• LAN connections establish mutual trust through a four-step mutual handshake. First-time pairing uses a SHA-256-derived 6-digit pairing code to prevent MITM attacks.
• LAN messages are end-to-end encrypted with X25519 ECDH key agreement, HKDF-SHA256 session keys, and AES-256-GCM/ChaCha20-Poly1305 AEAD.
• JWT access tokens are valid for 15 minutes. Refresh tokens are rotated immediately after single use, and old tokens are marked revoked to detect replay.
• The server does not persist messages, files, or clipboard contents. It only stores account and device metadata.

Development

This project uses a multi-repository structure. Each component is maintained independently:

Repository	Tech Stack	Description
colink-server	Go, Gin, GORM, PostgreSQL	Backend API server and WebSocket relay
colink-desktop	Tauri 2.x (Rust + React/TS)	Desktop client for Windows, macOS, and Linux
colink-android	Kotlin, Jetpack Compose	Android client
colink-castboard	TypeScript	Standalone CastBoard project
colink-frontend	Vue 3, TypeScript	Account and session management web frontend
CoLinkProtocol	Markdown	Protocol specifications and API documentation (hosted documentation: CoLink Protocol)

Clone the root repository and all sub-repositories into the same parent directory:

git clone https://github.com/CoLinkDev/CoLink.git
cd CoLink
git clone https://github.com/CoLinkDev/colink-server.git
git clone https://github.com/CoLinkDev/colink-desktop.git
git clone https://github.com/CoLinkDev/colink-android.git
git clone https://github.com/CoLinkDev/colink-castboard.git
git clone https://github.com/CoLinkDev/colink-frontend.git
git clone https://github.com/CoLinkDev/CoLinkProtocol.git

Build and Run

Each sub-project has its own setup instructions. See the corresponding README:

• Server — colink-server/README.md
• Desktop — colink-desktop/README.md
• Android — colink-android/README.md
• CastBoard — colink-castboard/README.md
• Frontend — colink-frontend/README.md