One of the many new features coming to iOS 7 that barely got a mention at WWDC is iBeacons. It's Apple's name for Bluetooth Low Energy (also known as Bluetooth Smart), which allows iOS devices to know where they are on a micro-location level.
Currently, iOS devices know where they are based on WiFi triangulation or built-in GPS, each of which is an approximation and only accurate to within a few meters. This is good when you're looking for an address, however it's not useful when you're looking for a store in a mall. iBeacons aims to change that by allowing the iPhone to talk to Bluetooth Low Energy locators located inside buildings.
AppleInsider has a great feature on how iBeacons can benefit users. The site says:
iOS 7's iBeacons can be used by app developers to do things like build an interactive tour of a museum, where the user's attention is directed to specific exhibits as they walk freely within the building.
In more general terms, the feature can also be used enable indoor navigation similar to GPS in settings such as an airport or underground subway station where GPS signals aren't available, or specifically to enhance navigational accessibility for the blind or users with other impairments.
For those interested in iBeacons or Bluetooth Low Energy, the entire feature is worth a read. And when iBeacons is unveiled in the fall with iOS 7, it is sure to make your iPhone a lot more useful as a navigation tool.