When Google extended Maps to indoor localization within shopping malls, new services immediately started to become within reach: navigation towards a specific article, directions towards a new promotion, cross-sales.
There are obviously limitations of the accuracy and reliability of indoor localization based on triangulation of WiFi and 3G network signals.
The potential of services linked to indoor localization, and the lack of cheap and reliable technology which enables it has pushed several companies to enter the domain.
Some of them propose to use additional hardware in the form of low cost RF beacons to be installed in the shop. These technique though require the installation of additional infrastructure, and often come with a hardware to be embedded into some form of portable device the consumer needs to carry around the shop to be localized (i.e. a basket, a kart, or barcode scanner).
Philips is now testing a new technology which enables indoor localization by means of LED fixtures and existing smartphones or tablets. The technology is developed in Philips Research, and promises to revolutionize the way we think about shopping.
Disclaimer: while I was part of the team which worked on this technology, this is not an official statement from Philips.