Evan Haning, wtop.com

UNDATED – GPS has gone indoors. Google’s new map feature will help Droid users find their way around airports, malls and big box stores.

Google Maps 6.0 can’t see through walls. It uses cellphone towers, WiFi hotspots and GPS with such precision it can tell if you’re taking the escalator up or down, All Things Digital reports.

The new Google indoor maps service is available at some airports in the U.S. (none around D.C. yet) and in Japan. It’s also available at various locations of some stores including Home Depot, Macy’s, Bloomingdale’s, and Ikea.

Google has not monetized the new mapping feature. A spokesman says the company’s current focus is on expanding the reach of indoor mapping by adding locations.

But with Google’s growing development of daily discount deals and mobile payments, All Things Digital says it is easy to imagine future targeted ads appearing on users’ Droids suggesting nearby places to shop.

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