Bluetooth is slow to reconnect after contact goes out of range and returns
Feedback from a tester: "Using Bluetooth only, when phone goes out of Bluetooth range, reconnection is slow (20 mins) or even does not reconnect at all. Very sporadic and unreliable behaviour with Bluetooth."
This could be caused by polling backoff - both devices will increase their polling intervals when there are no contacts in range.
More feedback from the same user:
"Using Bluetooth only, I noticed if I go out of range and do not turn off and back on my Bluetooth, and go back in range, reconnection is faster (~20 mins faster) than if I had toggled my Bluetooth. Is Briar Bluetooth reconnection when devices are back in range somehow assume some Bluetooth state that changes when Bluetooth radio is turn off and on again? To improve the back in range Bluetooth reconnection experience, could Briar detect that Bluetooth radio has been toggled while user was logged in and do something? Alternatively, have a "reset connection state" button that user can press themselves if Bluetooth takes too long to reconnect."