
Using animated bar codes, it's possible to send data over the air using only the camera. This app is the barcode decoder (receiver). An encoder (sender) can be seen at
cimbar.org.
With
CameraFileCopy it is possible to receive data over the camera as a one-way data channel. It does not use any antennas (wifi, bluetooth, nfc, ...) or other tricks. Notably, this means it works just as well in airplane mode.
The app reads animated
cimbar codes. Nearly all the interesting logic is from libcimbar – included via a git subtree. The sender component of cfc is a cimbar encoder -- such as
cimbar.org. Navigate to that website (or use libcimbar's
cimbar_send
to generate barcodes natively), open a file to initialize the cimbar stream, and point the app+camera at the animated barcode.