Air Kalon
Files through a camera.
Move a file from one device to another with nothing but a screen and a camera. No Wi-Fi, no hotspot, no cable, no internet, no pairing. It works in airplane mode, in a basement, and between two devices that have never met.
Free. macOS 14 or later, Apple silicon. Open Air-Kalon.dmg and drag Air Kalon into Applications. Release notes
How it works
Step 1
Show
Pick a file. The sender's screen plays it as a rapid stream of animated codes.
Step 2
Point
The receiver opens its camera and looks at the screen. Lock-on happens mid-stream, no handshake.
Step 3
Receive
Frames are recombined with a fountain code, so a missed frame costs a fraction of a second, never the file.
At a glance
- Transport
- Light. A display on one side, a camera on the other.
- Network
- None. No radio of any kind is used.
- Recovery
- Fountain coded. Any sufficient set of frames, in any order, rebuilds the file.
- Speed
- Up to 43 KB/s Mac to iPhone and 44 KB/s iPad to iPhone, measured end to end across 64 device runs.
- Integrity
- Every transfer is checked against its SHA-256 digest before the file is offered to you.
- Platforms
- macOS 14 on Apple silicon, and iOS 17 on iPhone and iPad. A standalone app today, becoming part of Kalon.
Questions
Asked, answered.
- Why not AirDrop or a hotspot?
- Both need the right pair of devices, awake and discoverable, or a password and a plan. Air Kalon needs a screen and a camera, which every device already has.
- What happens if my hand shakes?
- Frames get missed and the receiver simply catches the next ones. There is no retransmission, because there is no channel to ask on.
- How big a file can I send?
- One stream carries about 77 MiB at the default frame size, and up to about 157 MiB at the largest, within a 256 MiB limit per file or folder. Speed is the practical limit: at the typical 25 to 36 KB/s, a one-megabyte file takes about half a minute.
Intelligence on the device you already own.
Private by default, fast without a network, and free for macOS and iPhone.