These days, the only Estimote-supported software for scanning/monitoring proximity to beacons is Estimote Proximity SDK, which uses Estimote’s proprietary Estimote Monitoring technology/protocol:
https://developer.estimote.com/proximity/ios-tutorial/
https://developer.estimote.com/proximity/android-tutorial/
If you prefer to work with Eddystone, there are a few 3rd party options out there (e.g., Android Beacon Library, or Google Nearby Messages for iOS/Android). All of Estimote beacons still support broadcasting Eddystone packets, so it’s perfectly fine to use Estimote beacons/hardware and 3rd party software—many developers I know, and a few of our customers do it this way. (Just keep in mind that if you run into any problems with the 3rd party SDKs, e.g., can’t detect the beacons, or the results are unreliable/inaccurate, we might not be able to help.)