I would agree that my lifestyle probably is atypical for much of Australia but not so unusual for people in rural areas where you may have a full life but mainly contact people you know. The 15 minutes within 1.5 m is not a particularly natural occurrence with strangers. When I'm travelling, I might eat out, but I'm usually travelling alone and pick a quiet table well away from others where I can peacefully read my book whilst I wait for my meal.
The situation with Bluetooth is quite interesting. I'm curious to know more about how it is functioning within the app. I've had a bit to do with Bluetooth but prior to the introduction of "smart" Bluetooth. It's a different beast these days, with the ability to pair to multiple slaves simultaneously. I'm thinking the general principle is the same, wherein it sends out a general enquiry and any other device within range sends back name rank and serial number. Logically, I would think that the effect on battery life would vary enormously, depending on the situation. If your phone is flat out answering to interrogation by many other devices, that'll hammer the battery but not necessarily otherwise.
I'm also interested in the 1.5 m. Without triangulation, there's only really two ways distance could be calculated. One would be the way bats do it, but with radio waves, not sound waves and the other would be signal strength. I'm doubtful that a phone could handle the first and the second seems open to a lot of variables. It'd be interesting to hear from anyone who's more up on the technical side. There's a lot of potential complexities, such as sitting next to someone at a pub, but one of you orders a new drink every fourteen minutes and the connection is broken; or is it coughulative? Five 3 minute exposures throughout the day?
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