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A clever solution used by e.g. Shopkick is to play a very high-pitched sound of a certain frequency on the store sound system and pick that up with the device m
by adamjernst 15y ago
A clever solution used by e.g. Shopkick is to play a very high-pitched sound of a certain frequency on the store sound system and pick that up with the device microphone.
I don't know if Apple is using this here. I bet they're instead identifying it by store Wi-Fi, since Apple stores all have that already. But for stores without Wi-Fi, the sound system trick works well since all stores have sound systems already.
- mikeash 15y agoI doubt that either the store sound systems or the phone's microphones perform well at frequencies above the audible, though, so it may not be quite the drop-in solution that it appears to be at first.