How it works

From your SIM to your iPhone in three hops.

Your carrier delivers calls and texts to the SIM as usual. The gateway relays them to your iPhone over the network the two phones share.

The architecture

Caller

Any phone, anywhere

GSM / LTE

Your carrier

Same plan, same number

Voice call

LineFerry gateway

Android phone holding your SIM

Wi-Fi · audio + SMS

iPhone

Rings on the native call screen

Wake-up path When the iPhone app is closed, the gateway sends an Apple VoIP push so the call still rings.

Connection modes

Pick how your phones are connected to see exactly what works today.

A call reaches your SIM in the gateway. The caller hears normal ringing.
The gateway tells your iPhone, and sends an Apple VoIP push if LineFerry is closed.
Your iPhone rings on the CallKit call screen.
You answer; the gateway answers the real call and carries the audio both ways.

Restarts the relay within seconds after a crash, starts it on boot, and backs off if something keeps failing.

With no iPhone reachable for about a minute while off Wi-Fi, calls ring on the gateway itself; it switches back when an iPhone returns.

Pushes carry the gateway's network addresses, so the iPhone finds it again quickly after you change networks.

Gateway: Rooted Android phone with the LineFerry Magisk module and gateway app. Certified: Samsung Galaxy S10+.
Client: LineFerry for iPhone, iOS 17 or later
Call interface: Apple CallKit
Wake-up: Apple Push Notification service: VoIP pushes over HTTP/2
Transport: Local network today (same Wi-Fi or the gateway's hotspot); internet relay in development
Messaging: SMS send and receive
Resilience: Supervised relay, automatic restart, local fallback ringing
Multi-device: One gateway ringing several iPhones: in testing
Encryption: Calls, texts and control messages encrypted between the gateway and paired iPhones (ChaCha20-Poly1305)