mDNS / Bonjour
Zero-config peer discovery via multicast DNS. Certificate fingerprint distributed over the discovery channel for Trust-On-First-Use — no CA, no account, no cloud lookup.
Peer-to-peer · End-to-end encrypted · No cloud
Your Files.
Direct. Private. Instant.
Transfer files between Mac, Windows, iPhone, Android and any browser. Same app, same experience — no accounts, no uploads, no waiting.
macOS
E2E
Windows
iOS
Android
macOS Windows iOS Android
Why DropLink?
Everything you need to share files — nothing you don't
DETAIL
End-to-End Encrypted
End-to-end encryption on every transfer: QUIC with TLS 1.3, ed25519 device identity. No server ever sees your data.
Every byte leaves your device encrypted. On LAN, DropLink uses TLS 1.3 over QUIC with ECDSA P-256 certificates and SHA-256 TOFU fingerprints distributed via mDNS. For internet transfers, TLS 1.3 with ed25519 device identity + BLAKE3 hash-tree verification ensures integrity end-to-end. Cipher suites are auto-selected: AES-NI on x86 and ChaCha20-Poly1305 on ARM for optimal hardware acceleration. Not even our relay servers can decrypt your traffic — they only see encrypted bytes.
DETAIL
QUIC-Powered Speed
Modern UDP protocol with BBR congestion control. Faster and more stable than TCP on WiFi.
DropLink speaks QUIC (RFC 9000) — the modern transport behind HTTP/3. Benefits over TCP: a 1-RTT handshake, session resumption via 8 pre-generated TLS 1.3 tickets, no head-of-line blocking across streams, built-in TLS 1.3. The transport is tuned for LAN WiFi 6: MTU 1472 bytes, BBR congestion control with 1 MB initial window, 2ms initial RTT (vs Quinn's 333ms default), reduced ACK frequency. Throughput follows what your network allows — the transport holds the maximum rate instead of sawtoothing the way TCP often does.
DETAIL
LAN & Internet
Auto-discovery on your local network. Peer-to-peer via internet with NAT traversal when you're apart.
On the same Wi-Fi, devices find each other in seconds via mDNS/Bonjour (service type `_droplink._udp.local.`). Heartbeats every 5s keep the peer list fresh; a peer that misses a single ping is removed immediately, so a device that leaves the network disappears in about 10s. When you're on different networks, DropLink registers with our signaling server to exchange iroh NodeIDs, then performs NAT hole-punching for a direct P2P tunnel. If the NAT is too strict (symmetric NAT, corporate firewalls), traffic falls back to an end-to-end encrypted DERP relay. Same interface, seamless switch.
DETAIL
Cross-Platform Native
Native apps on macOS, Windows, iOS and Android — plus a Web UI that works in any browser.
Not a wrapped webapp: DropLink ships native code on every platform. macOS uses SwiftUI with an XPC service for crash isolation and USER_INTERACTIVE QoS threading. iOS shares the same UI code and adds a Live Activity widget for lock-screen progress. Windows runs on Tauri v2 with a Vue.js frontend, system tray integration, autostart, and native notifications. All share the same Rust core (`staticlib`/`cdylib`) — the exact same QUIC, iroh, crypto, and transfer engine running on every device.
DETAIL
AirDrop-Style Requests
Accept or reject before the transfer starts. You stay in full control of what you receive.
Before a single byte lands on your device, DropLink shows you exactly what's coming: sender name, file names, total size. You accept or reject — your choice. During the transfer you see live progress (EWMA-smoothed speed, ETA) and can cancel anytime. The engine uses lock-free AtomicU64 trackers for zero-overhead monitoring. Up to 5 simultaneous downloads and 3 uploads per peer by default, with adaptive backpressure. No silent uploads, no auto-accept surprises.
DETAIL
No App Needed to Receive
Built-in Web UI — the receiver just opens a link in any browser to download files.
Every DropLink instance runs a local HTTP server (axum v0.8) serving an embedded Web UI compiled into the binary. Share a link, a QR code, or a short code — the receiver opens it in Chrome, Safari, Firefox, or any browser. Downloads support HTTP Range requests, so they're resumable, parallel, and can handle files of any size. Optional password protection (SHA-256 hash) + time-limited tokens. Perfect for sending files to anyone without asking them to install anything.
Direct, On-Wire
QUIC over UDP with TLS 1.3 built-in. 1-RTT handshake, session resumption with 8 pre-generated tickets. BBR congestion control tuned for WiFi 6, 64 MB receive window, MTU probing up to 1472 B.
NAT-Traversal via iroh
When off the same LAN, an ed25519 device identity negotiates a direct path through NAT using the QUIC/TLS 1.3 handshake. Transport stays peer-to-peer, end-to-end encrypted.
Opaque DERP Tunnel
If hole-punching fails, traffic falls back to a DERP relay as encrypted TLS 1.3 pipe. The relay sees ciphertext only — it cannot read, alter, or log your file content.
No Account, No Log
No sign-up, no email, no telemetry. Your public IP is never published to third parties. Optional password protection with per-session tokens and brute-force rate limiting.
BLAKE3 Verified Streaming
On remote transfers, every chunk is verified in-flight against a BLAKE3 Bao tree. Tampered bytes are rejected on arrival — even a compromised relay cannot silently alter what iroh delivers.
How It Works
Three transfer modes, picked automatically — always end-to-end encrypted
LAN · QUIC
Discovery on your Wi-Fi
Two devices on the same network find each other automatically via mDNS and transfer files directly using QUIC over UDP. Zero servers involved.
- 1
Automatic discovery
DropLink announces itself on the network via mDNS/Bonjour (service `_droplink._udp.local.`). Other devices appear in the peer list within seconds.
- 2
AirDrop-style request
Pick a recipient, drop your files. The receiving device shows an accept/reject prompt before any data starts flowing.
- 3
QUIC transfer, TLS 1.3
Once accepted, files stream directly peer-to-peer over QUIC with TLS 1.3 encryption. BBR congestion control, 1-RTT handshake, full network speed.
DropLink
DropLink Vicini
iPhone 16 Pro
● Disponibile
DropLink
DropLink Vicini
MacBook
● Disponibile
Trasferimento in arrivo
report.pdf · 2.4 MB
report.pdf
32 MB/s · TLS 1.3
Remote P2P · iroh
P2P across the internet
When devices are on different networks, DropLink uses iroh for NAT traversal. A signaling server helps peers find each other — then data flows directly between them, encrypted end-to-end.
- 1
Signaling & share code
The sender registers with our signaling server (WebSocket, authenticated) and gets a short share code. No file metadata is exposed.
- 2
NAT hole-punching
Both peers exchange connectivity info through signaling and attempt NAT traversal. In most cases, they establish a direct connection — no relay needed.
- 3
Direct P2P, TLS 1.3
Files stream directly between the two devices using TLS 1.3 with ed25519 device identity. BLAKE3 integrity verification built in.
DropLink
report.pdf
Drop files
Share code
A 7 K - 2 M 9
Signaling · iroh
DropLink
Enter share code
-
P2P · TLS 1.3
Relay fallback
If direct P2P fails (symmetric NAT, strict firewall), DropLink automatically falls back to an encrypted DERP relay — traffic is still end-to-end encrypted, the relay only sees encrypted bytes it can't read.
Web UI · Zero install LAN
No app needed to receive
The receiver doesn't have DropLink? They open a link in any browser and download files from the sender's built-in Web UI. Perfect for sharing with anyone.
- 1
Sender starts sharing
DropLink runs a local HTTP server (axum) and generates a secure link or QR code. Optional password protection with SHA-256 hash.
- 2
Open the link in a browser
Chrome, Safari, Firefox — any modern browser works. On LAN the link points directly to the sender. Remote transfers route through our download gateway.
- 3
Download with Range requests
Browser downloads via HTTP/1.1 with Range support — resumable, parallel, standard. The sender can cancel or revoke access anytime.
DropLink
report.pdf
Drop files
Open in browser
192.168.1.42:7878
DropLink
report.pdf
2.4 MB
HTTP · Range requests
Free on all platforms
Get DropLink
Transfer files between Mac, Windows, iPhone, Android and any browser. Same app, same experience — no accounts, no uploads, no waiting.
Browser · No install needed
Encrypted
Transport protocol
Frequently Asked Questions
How secure is DropLink?
DropLink uses end-to-end encryption on every transfer. Local transfers use TLS 1.3 with QUIC. Remote transfers use TLS 1.3 with ed25519 device identity. No server — including ours — can read your files. Optional password protection adds another layer.
Do both devices need DropLink installed?
No. Only the sending device needs DropLink. The receiver can use any browser — DropLink includes a built-in Web UI that lets anyone download files by opening a link. No app installation required on the receiving end.
Is there a file size limit?
No built-in limit. DropLink transfers files directly between devices, so the only constraints are your network speed and available storage. This makes it ideal for large files like videos, design assets, or software builds.
Which platforms are supported?
DropLink is available natively on macOS (App Store), Windows (Microsoft Store), iOS (App Store), and Android (coming soon). Files can be received on any device with a browser, including Linux and ChromeOS.
Does it work over the internet?
Yes. DropLink automatically detects whether devices are on the same network (LAN) or remote. For remote transfers, it establishes a direct peer-to-peer connection with NAT traversal. If direct connection isn't possible, an encrypted relay ensures delivery — but your files are always end-to-end encrypted.
Can I send multiple files or folders?
Yes. When you select multiple files or a folder, DropLink automatically compresses them into a ZIP archive with adaptive compression — fast for large files, standard for text. Progress is shown in real-time with speed and ETA.
See how DropLink compares