iOS Beacon is a simple iOS application that allows your iPhone or iPad to broadcast as an iBeacon. If you have a spare iPhone/iPad lying around, you can install this on your spare device to use for testing and developing iBeacon applications.
Though there were many other iBeacon broadcasting sample applications, they were mostly outdated, complex and had issues compiling. This one is pretty straightforward with no bells and/or whistles. Just an application that acts as a broadcasting agent.
You will still need an app that will receive the broadcast, and there is a couple out there that works (for me, at least). Beacon Scanner by Matt Nedrich is the one I'm using. You can read his guide on interacting with iBeacons in iOS using Swift here.