Rattlegram
Transceive short UTF-8 text messages over COFDMTV encoded audio signals.
Find Rattlegram on the Google Play Store
You can install Rattlegram for free from the Google Play Store:
https://play.google.com/store/apps/details?id=com.aicodix.rattlegram
Rattlegram is based on open-source software:
OFDM modem implementation and specification:
https://github.com/aicodix/modem
BSD Zero Clause LicensePolar list and ordered statistics decoding:
https://github.com/aicodix/code
BSD Zero Clause LicenseDigital signal processing:
https://github.com/aicodix/dsp
BSD Zero Clause License
Privacy Policy
To be able to decode COFDMTV encoded text messages, Rattlegram needs access to the microphone.
Having access to the microphone is considered to be a sensitive permission and you
have the right to know what Rattlegram does with that access:
The data recorded from the microphone is only used to feed the COFDMTV decoder
and spectrum analyzer for the visualization of its frequency content.
Rattlegram uses a very small temporary buffer in volatile memory and constantly
overwrites that buffer with new data from the microphone.
The resulting text message from the COFDMTV decoder is the only data that gets stored
in persistent storage on your device.