Voyager

Android screen mirroring on Windows, without the setup ritual. Plug your phone in and the mirror opens. Go wireless over the phone's own hotspot, no wireless debugging toggle, no shared WiFi.

Built on scrcpy and a pure Dart adb client. For Flutter and Android developers who test on real hardware all day.

Windows only for now. Current version: v0.3.0.

The problem this solves

scrcpy's wireless path expects two things: Android's wireless debugging enabled, and your PC and phone on the same WiFi network.

That breaks the moment you are on the phone's hotspot, which is the common case when you are testing away from a desk. A phone cannot be a hotspot and a client on some other WiFi at the same time. So you are back to a cable, or to typing adb tcpip 5555 and hunting for an IP by hand every session.

Voyager automates the legacy tcpip path instead. On a hotspot the phone is the default gateway, so the daemon reads the gateway from the routing table and connects to it. No toggle, no IP hunting, and the same code path also handles the plain same WiFi case.

What works today

All three verified on a Pixel 10a, 25 July 2026.

	Status
USB plug-and-play: plug in, mirror opens in about 1 second	Working
Auto-launch on device ready, no clicks	Working
Wireless over the phone's hotspot, survives unplugging USB	Working
Flutter UI and tray icon	Not yet, see roadmap
Installer with bundled binaries	Not yet, see roadmap

Requirements

• Windows 10 or 11
• Flutter SDK on PATH (it ships Dart, which is what actually runs). Check with flutter doctor.
• adb and scrcpy on PATH, or their paths set in config.json. Bundled binaries come in a later milestone.
• USB debugging enabled on the phone

Run it

There is no installer yet. Clone and run the daemon.

# fetch deps and confirm the adb client works on your machine
cd packages\core
dart pub get
dart test

# start the daemon
cd ..\daemon
dart pub get
dart run bin\daemon.dart

Plug your phone in. You should see the device name and serial appear, and a scrcpy window open.

If adb is not on PATH, pass it directly:

dart run bin\daemon.dart "C:\platform-tools\adb.exe"

The daemon reads stdin while it runs:

Key	Does
w	go wireless
u	back to USB only, closes port 5555
l	list devices
q	quit

Config lives at %APPDATA%\scrcpy_gui\config.json and is created on first run. It holds the adb path, the scrcpy path, and an autoLaunch flag.

Going wireless

1. Phone on USB. Type w.
2. The daemon runs tcpip 5555 and caches the phone's WiFi IP.
3. Enable the phone's hotspot and connect your PC to it. Unplug USB.
4. The daemon reads default gateways from route print and tries adb connect on each, then falls back to the cached WiFi IP.
5. The mirror keeps running.

Security: port 5555 open means anyone on that network can adb into your phone. On a phone hotspot that is a network of two, so the exposure is small, but it is real on a shared WiFi. Press u when you are done to close it.

How it is put together

Three layers, each independently testable. The daemon does the work; the UI, when it lands, is a thin dashboard on top of it.

UI (Flutter Windows)      tray, popups, settings        milestone 5
        |  NDJSON over loopback TCP
Daemon (Dart CLI)         device tracking, launching,   working
        |                 wireless orchestration
Core (pure Dart)          adb client, wire protocol     working
        |  TCP 5037
adb server

• packages/core speaks the adb server's binary protocol directly over TCP 5037. No parsing adb.exe stdout, no subprocess per query. AdbClient exposes a trackDevices() stream for instant device events plus tcpip(), connectDevice(), and shell(). FakeAdbServer lets the whole thing be tested without a phone or a real adb server. Pure Dart, no platform deps, so it is usable as a standalone library.
• packages/daemon watches the device stream, spawns and kills scrcpy per device, and runs the wireless handoff. Headless, so it is easy to debug and will later sit behind the tray icon.
• packages/ipc is the NDJSON message contract between daemon and UI, plus a loopback socket server and client. Scaffolded and importable, not wired into the daemon yet. See packages/ipc/INTEGRATION.md for the schema.
• packages/ui is empty until milestone 5.
• vendor/ is where bundled adb and scrcpy builds go for packaging. Not committed.

Longer writeups: ARCHITECTURE.md for layers, data flow, and the reasoning behind each decision. PROJECT_STRUCTURE.md for a file by file guide.

Tests

cd packages\core
dart test
# 21 passing: 7 protocol unit tests, 8 fake-server integration tests, plus the rest

The daemon has a handoff test scaffold that is currently skipped, waiting on milestone 4.

Roadmap

• Milestone 4: one-step handoff command. Type h and an active USB mirror moves to wireless, new window up before the old one closes.
• Milestone 5: Flutter Windows UI. Tray icon, device popup, settings. IPC replaces the stdin commands.
• Milestone 6: bundled adb and scrcpy, Windows installer, startup integration, code signing.

Known limitations

• No UI. Terminal only.
• No installer. Clone and run.
• adb and scrcpy are not bundled yet.
• Windows only. packages/core is portable, but the launcher and tray are not.

License

TBD.

Credits

All the actual mirroring is scrcpy by Genymobile. This project is a Windows front end and an adb automation layer around it.

Built by Babul Raj Singh.