distance between android and iphone

Question

I am looking for a way to transmit data when two phones are close by. This needs to be cross platform so I cannot use NFC or iBeacon. I plan on using allJoyn to send informa

Answer 1

So the best way that I found to do this is to use the accelerometer to tell when two devices bump then I get the bluetooth signal strength of the nearest device, if that falls into a certain value then they are touching.