The AirPort devices, and I have like 5 of them, are the most boring devices I have. Meaning that I haven't had to touch them in over 3 years, some approaching 5 years since I plugged them in. The last software upgrade was years ago too, so no reboots with that even.
The wifi mesh capability is one of the most invisible and useful features of the AirPort devices. I searched up and down to enable this feature and turns out there's nothing to configure. Just name all your wifi access points the same and put in the same password, and your Macs, iPhones, iPads just automatically switch to the nearest base station. The base stations know about each other too so there isn't any kind of signal interference, they automatically switch channels so that there's no conflict. It's pretty amazing tech that Apple doesn't even talk about.
Unfortunately Android or Windows laptops don't seem to be able to seemlessly switch between base stations, Airport devices or not. They just latch onto the original wireless station and don't switch to a stronger signal even when available.