No Wi-Fi. No Bluetooth. No cables. No accounts. A receiver looks at a sender's screen and the file is there. The medium is photons, and photons only travel one way.
The sender — a Linux box, a browser tab, your desktop — turns your file into a stream of color-tile barcodes that animate on a screen. The receiver's camera reads the light. The bytes reassemble. Nothing else moves between the two devices.
The desktop app bundles the encoder offline — no browser, no network, works on an air-gapped machine. Or skip the install and use the web sender.
"A one-way road for files that must cross anyway."
Configs, logs, keys, and documents still have to move in and out of isolated machines — and a USB stick is the riskiest way they do it. A screen and a camera carry small files across the boundary, and light physically guarantees nothing travels back.
"Send from anywhere; receive on the phone in your hand."
Generate a cimbar stream from a Linux server, a browser tab, or your desktop. Your iPhone scans the screen and the file lands in your camera roll — without installing anything on the sender side.
"One room, one beam of light. No record exists."
Journalists protecting sources, attorneys handling sensitive evidence, anyone who needs to move a file onto their phone without leaving traces in cloud accounts, IP logs, or pairing histories. Open a sender in any browser; the medium is the room itself.
OpticDrop builds on libcimbar (MPL 2.0). The protocol, error correction, and every modification we ship are public. In security-sensitive contexts you should never trust a closed transfer protocol — read the code, compile it yourself. We expect you to.
The paywall never blocks a file: on the free tier every transfer still completes, at standard speed. Pro removes the pacing on large files. That's the whole deal — no locked features that decide success or failure.
Unlimited transfers at standard speed. Pacing on the receiver side, never a hard stop — the file always arrives.
Peak up to 3× faster on the same hardware. Only applies to files over 1 MB — small files are always full speed for everyone.
Every install includes 5 free high-speed transfers. Feel the difference first; upgrade only if it matters to you.
The full transfer tool. Not a trial.
The high-speed channel, for people who transfer every day.
Everything in Pro, forever. One purchase, zero renewals.
On the high-speed path, current iPhones sustain about 285 KB/s with bursts past 400 — a 1 MB file lands in 4–6 seconds. The free tier paces large files to a standard rate instead. A single transfer caps at 33 MB.
Any screen. Our web sender at opticdrop.app/send runs in every modern browser with nothing to install; the libcimbar CLI covers macOS, Linux, and Windows — including air-gapped machines. Your iPhone receives.
Use AirDrop when both sides are Apple devices that are allowed to talk. OpticDrop is for everything else: the sender isn't an Apple device, radios must stay off, or you don't want any pairing record connecting the two machines.
There is no network link to encrypt — nothing leaves the room, so there is nothing to intercept remotely. The beam is visible, though: anyone who can film the screen can capture it. Treat it like a conversation held in the room.
No. No account, no sign-in, no telemetry. The app works in airplane mode — that is rather the point.
Nothing breaks. Fountain coding means the sender streams endless fresh combinations of the data, so the receiver needs enough frames, not specific ones. Hold roughly steady and the transfer completes.
Yes. Completing a transfer is free forever — that is a design rule, not a promo. Anything that decides success or failure stays free; Pro only changes how fast large files arrive.
Subscriptions are billed by Apple, so cancellation is in iOS Settings → your name → Subscriptions — we never touch your payment details and cannot stop you. Lifetime never renews, so there is nothing to cancel.
Files over 1 MB. The free tier paces decoding on large files to a standard rate; Pro removes the pacing, with peak throughput up to 3× on the same hardware. Small files are always full speed for everyone.