CastLink is an Android LAN screen-casting app: sender and receiver in one APK, plus an iOS AirPlay receiver. Cast your phone screen to a TV/box, mirror an iPhone via AirPlay, or push any file to another device — all on your local network, no cloud, no account.
Install CastLink and open it. The standby screen shows:
- A QR code — scan it with any phone to open the file-upload page
- A 4-digit PIN — needed for every cast or mirroring connection
- The device's Wi-Fi name and IP address
Leave the app on this screen. That's it — it's now discoverable.
- Make sure the iPhone and the receiver are on the same Wi-Fi.
- Open Control Center → Screen Mirroring.
- Pick the CastLink device name (shown on the standby screen).
- Enter the 4-digit PIN shown on the TV.
The TV plays your iPhone screen fullscreen. Disconnect from Control Center when done.
If the iPhone asks for a PIN every few seconds and never connects, check that CastLink is still in the foreground on the receiver and both devices are on the same network.
- Open CastLink → Cast this screen.
- Pick the receiver from the discovered devices list (or tap Enter IP manually).
- Enter the receiver's 4-digit PIN.
- Allow screen capture when the system dialog appears.
Your screen is mirrored at 720p/30fps. Tap Stop in the notification to end.
On the receiver's standby screen:
- Scan the QR code with any phone, or open
http://<receiver-ip>:8756/in a browser. - Choose any file to upload — video, audio, APK, documents, anything.
- The receiver handles it automatically:
- Video/audio → opens in the built-in player
- APK → asks to install (needs "install unknown apps" permission)
- Other files → opens with the system's default viewer
Received files are listed in the app's Media tab, tap to open again.
CastLink checks for updates automatically (once a day, toggle in Settings). When a new version is found, it shows what's new — tap Update now to download and install.
You can also check manually: Settings → Online update → Check for updates.
- Device name: the name shown to other devices (AirPlay list, discovery)
- PIN: view or regenerate the 4-digit PIN
- Language / 语言: Chinese or English, switches instantly
- Download mirror: if updates download slowly, switch the mirror source
- Android sender + Android receiver + AirPlay receiver, one APK
- AirPlay: PIN pairing (SRP), FairPlay handshake, H.264 + AAC/ALAC
- File cast over HTTP: any file type, auto-routed on the receiver
- OTA updates with China-friendly mirrors
- NEBULA UI: phone portrait/landscape, TV and car head-unit layouts
- Chinese/English, instant switch
- Built-in crash reporter and diagnostics
- DRM content (Netflix, Disney+, Apple TV…) can never be cast — platform restriction, not a bug.
- Android sender is 720p/30fps video-only for now.
See THIRD-PARTY-NOTICES. AirPlay crypto derived from PhairPlay (Apache-2.0). No GPL code.
Apache-2.0.