I've tried using bluetooth in a museum exhibition before and noise from wifi and other equipment rendered it pretty hopeless... but may have been the modules I was using...

Flawless at home/office. Useless on site

This app indicates that existing Android and iPhones can already act as receivers. Can you (or anyone more familiar with the tech) verify that is true?

https://stackoverflow.com/questions/27294649/i-want-ble-broa...

Receivers of BLE broadcast packets? Yes, that's how devices are discovered. It's just that you can also stuff those packets with a payload and transfer data (one way) without a connection.