In with the old.

As two children walk down a busy city street, they look slightly out of place.  The city is very modern, with cement towers and towering tall buildings.  On the other hand, the children appear to have come from a different sort of place. Dressed in old-fashioned clothing, perhaps from Germany or another European nation, the kids contrast against the modern city.  As the AT&T commercial progresses, the viewer sees that although the kids look like they are from a different time period, they presumably have up to date technology as they pull out a phone.  The contrast between the different worlds emphasizes the importance of the AT&T phone and its easy accessibility.
Unlike the modern city, the children appear to be of a less technologically inclined world.  From the beginning of the commercial, the children drop breadcrumbs to mark their tracks, much like in the old fable of Hansel and Gretel.  The old european outfits of the boy and girl also support the allusion reference to Hansel and Gretel.  Just like in the story, the boy and girl end up lost in an unfamiliar area and the breadcrumbs disappear.  Using this commonly known connection allows viewers to connect to the commercial and understand the ease and importance of the AT&T phone with mapping capabilities.  The contemporary city allows the viewer to relate to a familiar setting while the allegory of Hansel and Gretel connects the viewer to a literary and childhood memory.  By reaching viewers on multiple levels, the commercial tries to better showcase the AT&T product and make the viewers connect with the product through their childhood memories and desire for new technology.