This Estimote Ionic Plugin is the right starting point if you want to build an Ionic app that uses the "ranging“ functionality of iBeacons of Estimote Beacons. Please see: https://developer.estimote.com/ibeacon/tutorial/part-3-ranging-beacons/

Beacon ranging provides fine-grained data about beacons detected nearby, as opposed to monitoring’s coarse-grained “inside region” and “outside region.” The data includes exact UUID, major, and minor values of ranged beacons, as well as proximity estimations.

Proximity estimations are based on received signal strength, and are good to roughly determine if the device is close to or far away from a beacon. Beacons are not meant to provide distance estimations!

Ranging works only when the app is running, and only requires the “when in use” authorization to access Location Services.

Usage:

1. Download and unzip the plugin and place it somewhere (the destination is going to be referred to as "/path_to_the_plugin/" in the next two steps)

2. Download the EstimoteSDK Framework (for iOS) from here: http://schneeweis.technology/EstimoteSDK/EstimoteSDK.framework.zip, unzip it and place it in the directory: /path_to_the_plugin/src/ios/Estimote

3. Add the plugin to your ionic app: ionic cordova plugin add /path_to_the_plugin/EstimoteSDKPlugin

Code: Please see the Starter App: https://market.ionicframework.com/starters/estimote-ionic-starter-app

(The screenshots are from this Starterapp using this plugin)

References: The Estimote Ionic Plugin and the Estimote Ionic Starter app have been used to create a museum app for iOS and Android: Search for "DomQuartier" in the Google Play and IOS App Store.