[crushthecurve]

We took a deeper look in an article linked in another comment on this thread.

One thing that's interesting to think about more deeply is how difficult it is to estimate proximity based on the combinatorial explosion of different hardware, individual device peculiarities, battery levels and environmental factors (walls, glass windows, partitions, ventilation).

The very limited data published appears like interesting preliminary field work which finds significant variability in signal strength across hardware, and rather than concluding proximity estimations are useful, ends in a plea for OEMs to release factory calibration data for their BLE implementations:

https://github.com/opentrace-community/opentrace-calibration...