Indoor mapping is taking off and it's a great little idea for retailers never mind, App developers or brands.
Using GPS (which really works outdoors only) you can locate the store and get directions which we are all used to. However, when you enter it, using Wifi and through a mobile App, you can then locate what you're looking for.
Macy's, the big New York American retailer, have just launched an App which does this, showing you all the various areas/retailers of the store. In a big retail environment, it helps you to get around but also points out things you may not have known were there. Bathrooms, Coffee shops, bag packing, customer service, retailers with special offers and so on.
In doing that, it of course, also allows advertisements as you literally pass by one shop based on where you're standing. It's not a tricky techy development area either - reasonably straightforward to produce and with Airports, huge audiences. 55 million people fly through Atlanta for example, 47m through Beijing, 40m through Heathrow and I think even Dublin airport has just under 20 million passengers.
With a "readership" level like that, makes it a lucrative business and high downloads of the App, just on airports alone. Charge a dollar for the Atlanta airport download alone and you've a 55m market. In fact, charge 10 cents.
But indoor mapping is a great possibility for retailers in shopping centres and malls. With a search function, say you search "jeans", it will mean that every visitor will be more likely to become a customer because they can find what they want easier and faster. And the App user, can be messaged.
As they say, there's an App for that.