Glint File Transfer

Glint moves files between two phones using only light.

One phone displays an animated code. The other watches it through its camera. That's the entire mechanism, no Wi-Fi, no Bluetooth, no cellular, no pairing, no account, and no server anywhere in between.

WHEN THIS IS USEFUL

Glint isn't trying to be faster than AirDrop. It's for the times when the usual ways aren't available, or aren't allowed:

• Somewhere with no signal, a basement, a plant room, a plane, a remote site, or during an outage
• Between phones that can't be paired, different ecosystems, a work device, a borrowed handset
• Where network transfer is against policy, secure facilities, isolated industrial systems, sites where personal devices can't join the network
• When you'd rather nothing touched a network at all

HOW IT WORKS

Choose a file on one phone. Point the other phone at the screen. Watch the progress climb, and the file appears, verified byte for byte.

Because the code is sent as a continuous stream, dropped or blurred frames cost nothing but a moment. Shaky hands, glare and reflections are all survivable: the receiving phone simply keeps watching until it has enough.

FROM A RECORDING

You can also film the animated code and decode the video afterwards. The person filming needs nothing installed, any camera will do and the recording can be decoded later, on a different device, by someone else entirely.

PHOTOS ARRIVE FASTER

Photos are optimised before sending, typically to a fifth of their original size with no visible difference on a phone screen. Documents and text files are compressed too. You're always shown both options with the time each will take.

PASSWORD PROTECTION

Anything on a screen can be read by any camera pointed at it. For anything private, protect a transfer with a code: the file, its name and its size are all encrypted with AES-256, and the code is never shown on screen, you share it with the other person yourself.

SEVERAL FILES AT ONCE

Send a set of photos or documents together and they arrive as a single archive, ready to unpack on the other side.

NOTHING IS COLLECTED

Glint has no network code in it at all. There is no account, no analytics, no telemetry, and no server. Your files go from one screen to one camera and nowhere else. The only permissions it asks for are the camera, to read the code, and Photos, to save what arrives.

REQUIRES TWO DEVICES

One phone sends and another receives. You can also test it with a single device by screen-recording a transfer and decoding the recording.