Shiny is a Xamarin Framework designed to make dealing with device & background services easy by bringing things like dependency injection, logging, and lots of utilities to bring your workflows to the background in friendly, testable, way!
Shiny isn't all about backgrounding, DI, RX, and all of that cool stuff. It actually provides a ton of utility functions as well.
Beacons are low powered IoT devices that emit a signal over Bluetooth advertising that contains a specific (and very small piece of data) that is like an address. You attach that address to a "location" of some type. They are like an invisible light house. If you have a device that can "see" those signals, you can find out how close you are to it.