Since beacons became available there has been an emphasis on new companies creating new systems that use beacons. Now that beacons are maturing we are starting to see existing apps and systems add beacon-triggered functionality.
A very recent example is the FileMaker platform that has added iBeacon geofencing. Two other examples are car mileage logging apps that turn on/off in response to beacons and the Motorola MOTOTRBO range of two-way radios that include beacon detection so that they can support indoor positioning.
These scenarios are very different and therein lies the opportunity. Many existing systems, apps, services and products can be extended to provide for features based on location. Instead of looking for new things, that might experience difficulty gaining traction, think about what you (or your partners) already have and work out if beacons can provide added value.