For those looking for an app which uses this technique (so called data-over-audio technology) look no further than Chirp https://www.chirp.io/ https://www.chi

For those looking for an app which uses this technique (so called data-over-audio technology) look no further than Chirp https://www.chirp.io/ https://www.chirp.io/ Enhance your products by integrating with Chirp™ - the world’s most trusted data-over-audio technology used by the leading brands in more than 90 countries