The key requirement is built-in NFC technology.
NFC stands for Near Field Communication. This is a proximity-based wireless communication. Differing from Wi-Fi or Bluetooth, NFC is limited to an extremely short range — this is why you need to hold your phone very close to the sensor to get a reading.
For Apple users
The FreeStyle Libre 2 app is compatible with iPhone 7 and newer models running iOS 11 or higher.
For Android users
Vively is not available on Huawei or other Android devices that don’t have Google Play Store
Android models that are not compatible with Vively include:
Xiaomi Redmi
Ulefone Armor 7 & Armor X7 Pro
Samsung Galaxy S6
Samsung Flip Z & Flip Z2
Samsung Galaxy A10S