iBeacon allows Mobile Apps to listen for signals from beacons and react accordingly. AltBeacon works the same way.
Eddystone-URL is a beacon broadcast format that sends out a URL to a user’s device. This beacon signal can be picked up by either the Physical Web app, or the Google Chrome Widget, which appears in your notifications tab in iOS.
iBeacon is native only for iOS, but compatible for both iOS and Android.
Eddystone is Android and iOS compatible.
iBeacon broadcast one type of data and a unique ID number (UUID, Major and Minor numbers).
Eddystone broadcasts three different types of data: a unique ID number (Eddystone-UID), a URL address (Eddystone-URL), and Telemetry packet (Eddystone-TLM)