PhoneView (phone-controller)

A tool to view and control phones from a laptop, and potentially remotely, for security clinics. The phone's owner has to unlock the phone and follow the steps to establish the connection, every time.

View and control a USB-connected phone from a browser. One small Python process on the host (Windows, Linux, Raspberry Pi, thin client) relays the phone's screen to a local web page and sends your clicks, drags and typing back to the phone.

The host never decodes or re-encodes Android video; it only copies packets, so a Raspberry Pi or Wyse 3040 is enough. The browser decodes with WebCodecs.

Install

Python 3.11+. Install it as a standalone tool, in its own environment:

pipx install phoneview          # or: uv tool install phoneview

pip install phoneview into a virtual environment works too. PhoneView pins pymobiledevice3 to 11.49.x. ISDi uses the same range, so ISDi users install both together with pip install "isdi-scanner[phoneview]" (see ISDi's README).

From a checkout, for development:

python -m venv .venv
.venv/bin/pip install -e .[dev]       # Windows: .venv\Scripts\pip install -e .[dev]

Platform pieces:

• Android: Android platform-tools (adb). Debian/Ubuntu/Raspberry Pi OS: sudo apt install adb (also installs the udev rules). Windows: install platform-tools and put adb.exe on PATH, or pass --adb C:\path\adb.exe. The scrcpy server (~90 KB) is downloaded once from the scrcpy GitHub release and checked against a pinned SHA-256; on an offline host pass --scrcpy-server /path/to/scrcpy-server-v5.0.1.
• iPhone: Linux needs usbmuxd (sudo apt install usbmuxd). Windows needs Apple's USB driver (the Apple Devices app or iTunes).

On the phone:

• Android: enable Developer options → USB debugging, plug in, accept the Allow USB debugging? prompt. On Xiaomi/HyperOS also enable USB debugging (Security settings), otherwise touches are ignored.
• iPhone: unlock, tap Trust, and turn on Developer Mode (the page walks you through it).

Run

phoneview                  # or: python -m phoneview

PhoneView prints a link like http://127.0.0.1:8000/?token=… and opens it in your browser. The token is new on every start; without it the page shows "Access denied". PhoneView detects whether an Android phone or an iPhone is plugged in and switches automatically. It can also be started from ISDi's PhoneView button (see below).

Using the page:

• Click = tap. Drag = swipe; the finger follows the pointer live. Ctrl+drag = two-finger pinch around the screen centre (Android).
• Mouse wheel scrolls (Android natively; iPhone via a short swipe).
• Click the screen, then type. Enter, Backspace, arrows and Escape (= Back on Android) work, and Ctrl+V pastes. The text box under the buttons does the same.
• Phone buttons (Back, Home, Recent apps, Power, Volume, Siri/Assistant) and Android actions (Notifications, Quick settings, Rotate, Screen off/on) appear only when the connected phone supports them.
• Stream settings adjusts resolution, fps and bit rate (Android), or screenshot size, quality, fps and bandwidth budget (iPhone) without reconnecting.

Useful options (phoneview --help lists all):

--platform auto|android|ios   restrict detection
--serial ID                   choose a device when several are plugged in
--max-size 1280 --max-fps 30 --bit-rate 4     Android video
--ios-video auto|stream|screenshot            iPhone video route
--width 480 --quality 65 --active-fps 3 --idle-fps 0.5 --bandwidth-mbps 1.5   iPhone screenshots
--tunnel | --rsd HOST PORT    iOS 17+ tunnel options (see docs/ios-mvp-notes.md)
--public-origin URL           allow a local reverse proxy's origin (tailscale serve)
--audit-log FILE              append who viewed which phone, and when (JSON lines)
--no-browser                  print the link only

Viewing from another computer: tailscale serve

PhoneView always listens on 127.0.0.1. For remote viewing, let Tailscale publish it inside your tailnet over HTTPS, on the machine the phone is plugged into:

tailscale serve --bg --https=8443 http://127.0.0.1:8000
phoneview --public-origin https://laptop.tailnet.ts.net:8443

Then open https://laptop.tailnet.ts.net:8443/?token=… with the token from the startup link. HTTPS also enables the browser's video decoder remotely.

• Use tailscale serve, never tailscale funnel: funnel publishes to the internet.
• Restrict who can reach port 8443 with a tailnet access rule (for example, only group:consultants to tag:clinic-laptop).
• Do not change the bind address; the token is not meant to stand alone on a network.

Without Tailscale, an SSH tunnel works the same way: ssh -N -L 8000:127.0.0.1:8000 user@host, then open the link locally.

Starting from ISDi

ISDi shows a PhoneView button when PhoneView is installed with it (pip install "isdi-scanner[phoneview]"), is on its PATH, or ISDI_PHONEVIEW_CMD points to it. Pressing it starts PhoneView on port 6201 if it is not already running, then opens it in a new tab, already signed in. When the consultant arrived through tailscale serve, the link points at https://<same host>:8443 (override with ISDI_PHONEVIEW_PUBLIC_URL). PhoneView stops when ISDi stops, including when ISDi is killed. For remote use, also serve that port: tailscale serve --bg --https=8443 http://127.0.0.1:6201.

Running as a service (Linux)

# /etc/systemd/system/phoneview.service
[Unit]
Description=PhoneView
After=network.target

[Service]
User=phoneview
ExecStart=/opt/phoneview/.venv/bin/phoneview --port 8000
Restart=on-failure

[Install]
WantedBy=multi-user.target

The service user needs USB access: membership of plugdev (Android udev rules) and access to the usbmuxd socket for iPhones.

How it works

browser (WebCodecs / JPEG, pointer + keys)
   │  one WebSocket: binary video/JPEG frames, JSON status + input
host: session layer (token sign-in, host/origin checks, one controller, backpressure, input validation)
   │  Backend interface: capabilities, video, input, setup actions
   ├─ Android: adb server protocol → scrcpy server on the phone → H.264 passthrough
   ├─ iOS 27+: pymobiledevice3 ScreenStreamServer (in-process, loopback) → HEVC passthrough
   ├─ iOS 17+: DVT screenshots → JPEG + CoreDevice HID
   └─ iOS 15–16: screenshotr / WDA MJPEG → JPEG + WebDriverAgent

• src/phoneview/server.py: app, security middleware, CLI
• src/phoneview/security.py: token sign-in, session cookies, host/origin allow-lists, audit log
• src/phoneview/session.py: WebSocket protocol (documented at the top of the file)
• src/phoneview/media.py: fan-out; video queues resync on key frames, JPEG is latest-wins with acknowledgements
• src/phoneview/events.py: the one input model every backend accepts
• src/phoneview/backends/: interface and USB auto-detection
• src/phoneview/android/: adb client, scrcpy protocol, backend
• src/phoneview/ios/: connection/tunnel, Developer Mode, HID, stream, WDA, backend
• src/phoneview/static/: index.html, viewer.js, viewer.css (no build step)

Robustness rules the code follows:

• Version pinning. scrcpy server 5.0.1 by SHA-256 (its protocol is internal); pymobiledevice3 >=11.49,<11.50 (CoreDevice APIs move between releases).
• Capabilities, not special cases. Each backend reports what works right now, and the page shows only those controls.
• Fallbacks. Android drops to a smaller size if the encoder refuses one. iPhone tries the live stream, then screenshots. A browser that cannot decode HEVC switches the iPhone to screenshots by itself.
• Recovery. Unplug/replug, viewer reload and settings changes reconnect on their own. Stale input never crosses a reconnect (generation numbers). Held fingers are released when the viewer leaves.
• Lightweight. Android runs the scrcpy server only while someone is watching, plus 10 s of grace. iPhone screenshots drop to the idle rate when nothing changes.

Security

Not covered: anyone with an account or malware on the host machine can use the phone through adb or usbmuxd directly, so use a dedicated, up-to-date host.

After each clinic session, remove the trust the phone keeps:

• Android: don't tick "Always allow from this computer". Afterwards, Developer options → Revoke USB debugging authorizations, then turn USB debugging off.
• iPhone: Settings → General → Transfer or Reset iPhone → Reset → Reset Location & Privacy (forgets trusted computers), then turn Developer Mode off.

Releasing to PyPI

The version lives in src/phoneview/__init__.py. To release, bump it, tag vX.Y.Z, and publish a GitHub release; .github/workflows/publish.yml builds, checks and uploads with PyPI trusted publishing. One-time setup: on PyPI, add a trusted publisher for this repository, workflow publish.yml, environment pypi.

To build and check by hand:

python -m build && python -m twine check dist/*

Tests

pip install -e .[dev]
python -m unittest discover -s tests
node tests/test_viewer_js.cjs
# Real browser against a fake phone (needs ffmpeg and `pip install playwright`):
python tools/browser_e2e.py
# Against a real phone, while phoneview runs (token from its startup link):
PHONEVIEW_TOKEN=... python tools/smoke_test.py --port 8000

What has and has not been verified:

Known limitations, to confirm on hardware:

• iOS 17+ touch without a media stream. pymobiledevice3 notes that some configurations ignore HID touch and keyboard reports unless a media stream is active. Home and the App switcher were confirmed on hardware earlier. Individual taps and drags in screenshot mode were not.
• Android rotation. For a fraction of a second after the phone rotates, taps can land at transposed positions, and scrcpy ignores a release sent with the old frame size.
• iOS 27+ live stream with no viewer. The stream keeps the phone awake and encoding until PhoneView stops. Android stops 10 s after the last viewer leaves.

Earlier iOS 17 hardware findings (HID behaviour, App switcher, timing) are kept in docs/ios-mvp-notes.md.

Troubleshooting

• "No Android device found" or "no permissions" (Linux): install adb from apt (it adds the udev rules), make sure your user is in plugdev, and replug the phone.
• Samsung: "stack corruption detected (-fstack-protector)" in the log: Samsung's encoder aborts when the scrcpy launch command reaches 255 characters (scrcpy #2841). PhoneView omits options already at their defaults to stay under the limit, and a test enforces it. If this appears again, run adb logcat -d -b crash and report the output.
• Android touches do nothing (Xiaomi): enable USB debugging (Security settings).
• Black screen on some Android apps: banking and DRM apps block screen capture. This is expected.
• "This browser cannot decode …": use a current Chrome, Edge or Safari, opened at http://127.0.0.1 or localhost, not a LAN IP.
• iPhone 16.x "Could not mount the Developer Disk Image": keep the phone unlocked with Developer Mode on. The first mount downloads the image from GitHub.
• WSL: USB devices are not visible inside WSL without usbipd passthrough. Run PhoneView on Windows directly, or attach the phone with usbipd attach.

License

Apache License 2.0. See LICENSE.