The tourguide who stops for coffee with you

While the material available is limited to a few cities so far (Sept 2015), the production values are high and the content is excellent.

Very easy to use (from my admittedly tech-adept viewpoint), gave me context for the city I was wandering around without disrupting my experience or requiring me to change pace for a shambling your group (or conversely speed to catch up if I lingered somewhere or stopped for a snack).

Had no issues downloading episodes on the hotel wifi and then wandering around with cell and data service turned off (gps alone is passive and can function without using cellular data, it is just slightly less accurate in that mode), which was very handy given extortionate roaming contracts. Would suggest looking at the map for each tour so as to cache the map locally to refer to later if you need it.

JaneintheFireplace about Detour - Immersive Audio Tours, v1.5.1