The best signal was had by hanging my phone from the ceiling. Since the phone itself was connected to the cafe Wifi, I couldn't use wifi to connect to the phone. So I shared the phone's (cafe wifi) internet over Bluetooth. (I didn't know that was a thing until I tried it!)

(I think I was able to connect to that with another phone and set up a wifi hotspot for all my devices... but it's been a while!)

Maybe it was something like a Raspberry Pi that he placed at that cafe? Curious that his Bluetooth had more reach than the Wifi itself though. Maybe with a directional antenna. Agree, would be interesting to know his setup.

Same here! Please provide some details, very curious.