Nectarlink

Your Android phone and your Windows PC, working as one.

One open-source app for notifications, messages, clipboard, files, screen mirroring and more between Android and Windows 11. Local-first, end-to-end encrypted, no account and no cloud.

Important

Nectarlink is in active development. The everyday features work end to end (notifications, clipboard, files, media) and mirroring, messages and calls are well along, but there are no releases yet. See Project status.

Why Nectarlink

Connecting an Android phone to a Windows PC today usually means combining several tools, each covering one part of the job:

Tool	What it covers	Where it falls short
Phone Link	Notifications, messages, calls, photos	Needs a Microsoft account; many features depend on the phone brand; little control over what syncs
KDE Connect	Notifications, clipboard, files, remote input	The Windows version trails the Linux one; no screen mirroring
scrcpy	Screen mirroring and control	Developer setup, command line, no other features
LocalSend	File transfer	Files only
Intel Unison	Phone integration	Discontinued

Nectarlink aims to replace all of them with a single app per platform that is fast, private and pleasant to use:

• Local-first. Devices talk directly over your network. Nothing goes through a server, and there is no account to create.
• Encrypted end to end. Every connection is authenticated with the device keys exchanged during pairing.
• Works with a normal phone. Everything useful works with ordinary Android permissions. An optional one-time setup ("Power Levels", no root) enables more, such as background clipboard sync and app windows.
• Native on both sides. A Windows 11 app built with Qt Quick and Rust, and an Android app built with Jetpack Compose, sharing one Rust core.

The full plan, including research, feature list, architecture and roadmap, is in docs/PLAN.md.

Project status

Nectarlink has finished Phase 1 of the roadmap (the everyday features) and is working through Phase 2 (mirroring, messages and calls). Everything below works end to end and is covered by tests; there are no releases yet.

Working today

• Pairing by scanning a QR code shown on the PC (or opening its pairing link with any camera app), or by picking a nearby PC and comparing a 6-digit code. Both methods authenticate both devices; a wrong code pairs nothing.
• Encrypted connections over the local network (QUIC through iroh), with automatic reconnection after restarts, sleep and network changes.
• Live status of each paired device: connection, round-trip time, battery (with charging source and estimated time to full when available), power level, a vector preview of the phone's measured front screen shape (aspect ratio, corner radii and camera cutout), and a glanceable Home summary of unread messages, missed calls and the latest photo or screenshot.
• Find my device in both directions. The phone rings on the alarm stream, even in silent mode.
• Lock, sleep or wake the PC from the phone (when the PC is offline, Wake sends Wake-on-LAN magic packets to its stored network addresses, and the PC's Settings shows whether its adapter has Wake on Magic Packet turned on), and links both ways: share a link from any phone app to open it on the PC, or send a copied link from the PC's tray to the phone.
• Notifications from the phone on the PC, as Windows notifications and in a feed in the app, with the app's icon. Reply inline, run their actions (such as "Mark as read") or dismiss them from the PC; what's cleared on one side is cleared on the other. Live Updates (Android 16 progress notifications with segments and milestone points, ongoing progress bars, and chronometer/countdown timers for rides, deliveries and timers) stay pinned at the top of the feed and update in place in both the app and the Windows notification without re-popping. When a notification or text has a one-time verification code, both the Windows notification and the card in the app get a Copy code button (or copy it to the PC clipboard automatically if you turn that on in Settings; one-time codes are never sent back or saved in history). Photos in messages and big pictures come along. Per app, choose whether they pop up, show only in the app, or stay hidden, optionally silence popups while the phone is in Do Not Disturb, and find the last day's notifications in History.
• Clipboard: text and images you copy on the PC are ready to paste on the phone. From the phone, send them with the Quick Settings tile, the share sheet or a button in the app (Android lets only the app in front read the clipboard). When a web link, street address, phone number, parcel tracking number or email address arrives from a paired device, Nectarlink offers a fitting context chip (Open, Open in Maps, Call, Track, or Email) right on the confirmation (can be turned off in Settings). Both apps keep an optional encrypted Clipboard history of the last 50 text and image clips shared between your devices (with search, copy again, pin, delete and clear all). Passwords that password managers mark private and one-time codes are never sent or saved in history.
• Files and folders in both directions, at Wi-Fi speed. On the PC, drop them on the window, pick them, or right-click them in File Explorer and choose Send to and your phone (a notification follows the transfer); on the phone, share them from any app or pick them in Nectarlink. They land in Downloads\Nectarlink on the PC and Download/Nectarlink on the phone, with progress, cancelling, and transfers that pick up where they left off after a dropped connection.
• Screen mirroring: see the phone's screen on the PC, in a window of its own, at up to 1920 pixels and 60 frames a second, hardware encoded on the phone, with the phone's sound playing on the PC (Android 10 and later; mute it from the window); Android asks each time. Turn on Control from your PC in the phone's Nectarlink settings to tap, swipe, scroll and type with the PC's mouse and keyboard (right-click is Back), or set up Wireless debugging there once for real touch (live dragging) and keys, with nothing else to install; Nectarlink turns Wireless debugging back on by itself after a reboot.
• Phone apps in windows on the PC: with Wireless debugging set up (Android 11 and later), pick any of the phone's apps (with a Recent row for the ones opened most recently) and it opens in a window of its own with its own taskbar icon, running on the phone beside whatever its screen shows and without popping the phone's keyboard up on its screen; resize the window and the app re-lays out to fit, its size and position are remembered for next time, and if it closes on the phone the window offers to open it again.
• Messages (SMS, MMS and chat apps) on the PC: one calm Messages inbox combining the phone's SMS/MMS conversations (without duplicating texts the SMS provider already gives) and Unified Conversations from RCS, WhatsApp, Telegram, Signal and other MessagingStyle chat apps that arrived while connected, marked by app with a filter and inline reply via RemoteInput. View pictures in MMS threads, drag an image into a thread or paste one from the PC clipboard (Ctrl+V) to preview and send it as MMS, start a new conversation (searching contacts as you type), copy one-time codes with one click, and open links.
• Calls and contacts: a Calls page with the phone's recent calls (grouped by day, missed calls marked, tap to call back or text), its contacts (favorites first, with photos and search), and a keypad to call any number from the PC through the phone. When the phone rings, see who's calling on the PC (with the contact's name and photo), and answer, decline or silence it from there; media playing on the PC pauses automatically when a call rings or is answered and resumes when the call ends. During the call, the PC shows how long it has been going and can hang up and change the volume; with Wireless debugging set up (Android 12 and later), also mute, switch to the speaker, hold and use the keypad. The call's audio stays on the phone. Calls nobody answered show as missed.
• Photos and videos: a Photos page on the PC with the phone's camera roll, screenshots and albums, grouped by day. View photos in the app (with arrow keys between them), open them in Windows Photos, copy a photo to the clipboard, or save one or many to a folder you pick (Downloads\Nectarlink by default). New photos and screenshots from the phone also pop up on the PC with a preview, ready to save or copy.
• Phone storage in File Explorer: mount the phone's storage under %USERPROFILE%\Nectarlink\<Phone name> using the Windows Cloud Files API (placeholders, on-demand download with progress when a file is opened, native sync icons). Browse folders, open files, drop new files in to upload them to the phone, rename, create folders, and delete (media files move to the phone's trash on Android 11+). Works with All files access or only the folders you pick on the phone, and is off by default on both sides with a clear prompt on the phone.
• Touchpad, air mouse, keyboard, voice typing and presentation remote: control the PC from the phone — a touchpad with one-finger move, tap to click, two-finger tap for right-click, two-finger scroll, double-tap-and-hold drag and adjustable speed; an air mouse where holding the pad and tilting the phone moves the PC cursor with its gyroscope (with hand-tremor filtering, smoothing and tap-to-click); voice typing with a Dictate button (tap or hold to talk) that uses the phone's speech recognizer (on-device where available) with live partial results and types into the PC's focused field; soft-keyboard typing with a bar of modifier and special keys (Ctrl, Alt, Shift, Win, Esc, Tab, arrows, Home/End, PgUp/PgDn, Del and shortcuts); and a presentation mode with Next/Previous slide (plus the phone's volume buttons while open), Start/End show, Black screen, and a hold-for-laser pointer that draws an accent-colored dot on the PC screen following the phone's gyroscope or finger. Off by default on the PC, with a one-time prompt the first time a phone asks and a per-phone toggle in Settings.
• Deck (macro pad) and PC audio: turn the phone into a Stream-Deck-style button grid for the PC, with multiple swipable pages, full-screen portrait and landscape layouts, haptic feedback, a live PC master volume slider, mute button and active audio output device indicator (both on the PC card on Home and in the Deck header), and live tiles that show whether PC media is playing, the speaker volume level, and whether the microphone is muted. Tiles are configured on the PC (in Nectarlink's Deck page, with drag-and-drop reordering, icons and colors): media controls, speaker volume and mute, microphone mute, Lock PC, Show desktop, Switch window, Screenshot, custom keyboard shortcuts, web links, text snippets, launching .exe/.lnk apps, and PC shell commands (gated behind a separate per-phone Run Deck commands permission that is off by default).
• Voice recorder: record with the phone's microphone (with a live level meter, pause and resume, timestamped markers, and recording that keeps going when the screen turns off) and send it straight to the PC. On the PC it lands in the folder and format you choose (Downloads\Nectarlink and M4A by default, or MP3, WAV or FLAC converted on the PC), with a .markers.txt file beside it when you add markers and a notification to open the recording or its folder. If the PC is offline, the recording waits on the phone and goes out as soon as it reconnects.
• Phone as a webcam: use the phone's camera in video calls on the PC (Zoom, Teams, Meet, OBS and the Windows Camera app) as Nectarlink Webcam. Start it from the phone or ask from the PC (the phone always confirms before the camera opens), switch between back and front cameras, toggle the flashlight, zoom (1×/2× or continuous slider), choose 720p or 1080p at 30 fps, and horizontally mirror the image on the PC. Includes a live preview in Settings even before the Windows 11 virtual camera add-on (MFCreateVirtualCamera media source) is set up.
• Phone controls on the PC: see and change the phone's Do Not Disturb, ringer mode (Ring, Vibrate, Silent), flashlight, media volume, screen brightness, Wi‑Fi (with a confirmation before turning it off) and Bluetooth from the PC's Home screen. Volume, Ring/Vibrate and the flashlight work out of the box; Do Not Disturb and silent mode use Notification Policy Access; screen brightness uses Modify system settings; and Wi‑Fi and Bluetooth unlock with Wireless debugging (which also grants the Do Not Disturb and brightness permissions automatically).
• Media both ways: what plays on the phone shows on the PC, in the app and in Windows' own media flyout (so the keyboard's media keys work too), and what plays on the PC shows in the phone's media controls, with artwork and a seek bar.
• Battery alerts on the PC when the phone runs low or is fully charged. Phone notifications follow Windows' Do not disturb (they wait in the app).
• Capability matrix: both apps compute which features work for a pair of devices and what would enable the rest, so the interface never offers something that can't work.
• Timeline: one searchable local history of everything that moved between your devices — files, folders, clipboard items (linked by ID to encrypted clipboard history so clip content is never duplicated in SQLite), opened links, saved photos, voice recordings, and screen mirroring / webcam sessions (with duration) — grouped by day, with filters by kind and device, Open, Show in folder, Copy, Send again, Remove, Clear all, and configurable auto-purge retention (default 90 days or 5,000 items).
• Windows app: home, messages, calls, photos, deck, timeline and settings, two themes in light and dark (Bloom, which takes its colors from the desktop wallpaper, My phone's colors synced live from the phone's Material You wallpaper seed, or a preset seed, and Graphite), Mica, a custom title bar with Snap Layouts, and a tray icon. In the background it unloads its window and caches (~27 MB private commit when started in the tray or ~60 MB after closing the window, with a ~5–10 MB active working set).
• Android app: pairing, home (with Timeline and Clipboard history) and settings, Material You colors (synced live to paired PCs), a background connection service, and an identity key protected by the Android Keystore.
• Connection Doctor on the PC: finds what keeps the phone from connecting (firewall, a public network, a VPN) and fixes what it can.
• Windows installer: installs for everyone on the PC, allows the app through Windows Firewall, starts it with Windows, and uninstalls cleanly. Each v* tag drafts a GitHub release with the installer and the signed Android app; both apps update themselves from published releases, checked against their SHA-256 sums.
• "Ping me when it's done" & command-line client (nectarlink): run nectarlink notify-when <pid> or nectarlink notify-when -- <command...> on the PC to watch a running process or command, show a live chronometer notification on the phone while it runs, and alert the phone when it finishes or fails (with its exit code and duration). Also supports scripting and development (send, clip, notify, pair, and more).

Next: talking on calls through the PC (Bluetooth), and the rest of the plan.

Screenshots

The Windows app has two themes: Graphite, ink on paper, and Bloom, soft and colorful. Both come in light and dark.

Graphite	Bloom

_{The phone's texts on the PC, and its screen in a window of its own.}

_{Pairing a phone: scan the code, or pair nearby with a 6-digit code.}

_{Screenshots are from the current development build. The connected phone is simulated with the command-line client (nectarlink --as-phone demo); the mirrored screen is the Android app on an emulator.}

How it works

 Android app (Kotlin, Compose)            Windows app (Qt Quick, Rust)
          │ UniFFI                                │ cxx-qt
          ▼                                       ▼
 ┌─────────────────────┐   QUIC (iroh),   ┌─────────────────────┐
 │  nectarlink-core    │◄────────────────►│  nectarlink-core    │
 │  pairing, sessions, │  end-to-end      │  pairing, sessions, │
 │  storage, features  │  encrypted       │  storage, features  │
 └─────────────────────┘                  └─────────────────────┘

• One core, two apps. Protocol, pairing, sessions, the trust store and the capability matrix live in Rust (core/) and run unchanged on both platforms.
• Identity. Each device has an Ed25519 key, encrypted at rest with Windows DPAPI or the Android Keystore. Devices are addressed by their public keys.
• Network. Local network only by default: discovery over mDNS, direct QUIC connections, no relay servers. Away-from-home connections are opt-in.
• Protocol. Versioned and documented in docs/protocol/v0.md: length-prefixed CBOR messages on QUIC streams.

Repository layout

core/
  nectarlink-protocol/   Message types, framing, pairing cryptography      (MPL-2.0)
  nectarlink-core/       Identity, trust store, pairing, sessions, features (MPL-2.0)
  nectarlink-ffi/        UniFFI bindings used by the Android app          (MPL-2.0)
  nectarlink-cli/        Command-line client for development and testing   (GPL)
desktop/
  app/                   Windows app: Rust host, cxx-qt bridge, QML UI     (GPL)
  vcam/                  Windows 11 virtual camera Media Foundation DLL    (GPL)
android/                 Android app: Kotlin and Jetpack Compose           (GPL)
assets/fonts/            Fonts both apps ship with                         (OFL-1.1)
tools/xtask/             Code generation (theme tokens) and checks
spikes/                  Technical experiments with their results
scripts/                 Build and check scripts
docs/                    Plan, decision records, protocol, design system   (CC BY 4.0)

Building

Nectarlink is not ready for everyday use; these steps are for development.

Requirements

Part	Needs
Core and CLI	Rust (stable, pinned in rust-toolchain.toml)
Windows app	Windows 11, Visual Studio 2022 Build Tools (C++), Qt 6.12 for MSVC 2022 x64
Android app	Android SDK (platform 37, NDK 30.0.16248370), JDK 17 or newer, cargo-ndk (see android/README.md)

Core, CLI and tests

cargo test -p nectarlink-protocol -p nectarlink-core -p nectarlink-ffi
cargo run -p nectarlink-cli -- --help

Windows app (with Qt's bin folder on PATH, or QMAKE pointing to its qmake)

cargo run -p nectarlink-desktop

Android app

cd android
./gradlew assembleDebug

Windows installer (with NSIS installed)

./scripts/package.ps1             # target\package\Nectarlink-<version>-x64-setup.exe
./scripts/package.ps1 -StageOnly  # just the app folder, as it ships

All checks (formatting, lints, tests, license headers, generated files, dependency policy), as CI runs them:

./scripts/check.ps1            # add -Android and -Arm64 for the full set

Documentation

• Project plan: research, features, architecture, roadmap
• Protocol v0 and the capability registry
• Architecture decision records
• Capability matrix and the core API
• Design system
• Qt + Rust feasibility results

Contributing

Contributions are welcome. Please read CONTRIBUTING.md first; for anything larger than a small fix, open an issue to agree on the approach. Contributions are accepted under the Developer Certificate of Origin, and everyone is expected to follow the Code of Conduct.

To report a security issue, follow SECURITY.md. Please don't open a public issue.

License

• Windows and Android apps, CLI: GPL-3.0-or-later, with an app-store exception
• Core libraries: MPL-2.0
• Protocol specification and documentation: CC BY 4.0

See LICENSE for which license applies where. The Nectarlink name and logo are covered by the trademark policy.