The guide technology only works on iOS devices so far, but The Verge understands that it will eventually support Android-toting guests as well. Indoo.rs expects the service to be available either late in the third quarter or early in the fourth (think September or October), although you won't want to plan trips around that estimate -- it's up to SFO to flip the switch. Whenever the beacons are ready for action, they should give many fliers a new level of independence.

[Image credit: Thom Watson, Flickr]