Bluetooth advertising software

hi, am looking for a bluetooth software that can push images / files at events. I have a bluetooth dongle already. When a viewer sees the sign, he/she will turn on his bluetooth device and the bluetooth software will automatically push a file to his device. It has to be able to multi task, e.g. when 4 people all turn on their bluetooth at the same time, it has to send the data to all the 4 devices one by one or simultaneously. if u have a working software, please provide demo or provide screen shots.