Afaik the HID Global app saves a key in the OS key store (at least on Android) and uses the locally stored key with NFC so you just need network access to enrol

Afaik the HID Global app saves a key in the OS key store (at least on Android) and uses the locally stored key with NFC so you just need network access to enroll a key. Not sure what vendor/app these things use (maybe it's all in house)