Vitaliy Alexeyev

synshell · Phone · synlink

Linking a phone and a computer

Links synshell devices — phone and computer — over USB and Wi-Fi: screen, input, sound, files, notifications, a shared clipboard and ssh phone without knowing addresses.

READMEAUR package: synshell-link-binAUR package: synshell-link-git

Features

  • Finds devices by itself — over the phone's USB cable (NCM network) and in the same Wi-Fi network; with both, one session stays, over USB (plug the cable in and the session moves to it).
  • Secure connection — QUIC over UDP with TLS 1.3, an ed25519 key per device and pinned fingerprints; independent streams, so copying files does not slow down the screen.
  • Pairing — over USB the computer agrees at once and the phone asks for one confirmation; over Wi-Fi a 6-digit code is shown on both screens. A computer with discoverable = false is not visible in Wi-Fi.
  • Screen — live view and control in synlink-view: only the changed areas are sent, large changes go as H.264/HEVC video from the hardware encoder of the other side (V4L2, VAAPI, NVENC), the rest is sent losslessly when the screen stops.
  • Sound — during the live view the device's sound plays here, and the local microphone appears there as “Microphone ”.
  • Input — mouse, touches, keys and text on the other device.
  • Files — the device's file system is mounted with FUSE and shows up under “Devices” in the file manager; drop a file on the link icon in the panel to copy it to the device's Downloads.
  • Notifications — notifications of one device appear on the other.
  • Shared clipboard — text copied on one device can be pasted on the other; secrets from the password manager are cleared everywhere when cleared at the source.
  • ssh — ssh phone or ssh <name> through the link, over the cable or Wi-Fi; without a system sshd the daemon starts a user one on 127.0.0.1.
  • Wi-Fi networks — after pairing, the phone offers to take over the computer's Wi-Fi networks (NetworkManager or iwd); passwords travel only after you allow it on the phone.
  • For developers and AI agents — the synlink command line and an MCP server for Claude Code: screenshots, taps, swipes, text, commands, logs, notifications, files and screen recording.

The phone shell shows “USB cable connected · shells linked” and the computer's card in the shade; settings are in “System Settings → Device link” ([link] in config.toml, applied on the fly). How it works inside: docs/LINK.md.

Install

synlink comes with the synshell-link package (the synlink daemon and the synlink-view window) — x86_64 and aarch64:

yay -S synshell-link-bin      # prebuilt
yay -S synshell-link-git      # built from source

Depends on synshell-core. Optional: openssh (ssh to linked devices), fuse3 (files of linked devices in the file manager). Part of the synshell metapackage: yay -S synshell-bin installs the whole desktop. From source: cargo build --release -p syn-link in the synshell repository.

The daemon starts with the session (/etc/xdg/autostart/synlink.desktop), one per user.

Command line

synlink status                 # this machine, the cable, devices
synlink pair accept phone      # answer a pairing request from the terminal
synlink shot phone -o a.png    # screenshot (PNG)
synlink tap phone 540 1200     # tap (screenshot pixels or fractions 0..1)
synlink swipe phone 0.9 0.5 0.1 0.5 300
synlink type phone 'hello'     # text into the focused field
synlink key phone ctrl+a       # key combination
synlink action phone back      # synwm action: back, shell home, shell shade…
synlink exec phone -- uname -a # command (streamed output, exit code)
synlink shell phone            # terminal
synlink logs phone -f -u synshell
synlink view phone             # live view window
synlink audio phone on         # sound of the live view (off — stop; --no-mic — without the microphone)
synlink mount phone            # files (usually mounted by themselves)
ssh phone                      # ssh inside the link

A device is a name, the start of its id, phone/desktop/laptop (if there is only one) or local — this machine.

Claude Code: claude mcp add synlink -- synlink mcp — tools devices, screenshot, tap, long_press, swipe, scroll, type_text, key, action, windows, exec, logs, notifications, read_file, write_file, record.

Settings

[link]
enabled = true        # daemon in the session
name = ""             # name for other devices (empty — the device model)
discoverable = true   # visible in Wi-Fi for pairing
notifications = true  # forward and show notifications
auto_mount = true     # files of linked devices in the file manager
clipboard = true      # shared clipboard
port = 47471          # UDP QUIC; discovery — port − 1

Part of synshell

synlink is one of the applications of synshell — a Wayland desktop environment in Rust for computers and phones, built on the syngui UI framework.

License

GPL-3.0-only