Question about Xiaomi Smart Band 9 Pro

The Smart Band 9 Pro (44 mm) is compatible with the iPhone 11 as it supports devices with iOS 12.0 and higher. You can connect it to your iPhone via Bluetooth 5.4 and use the Mi Fitness app from the App Store to utilise its functions. The iPhone 11 fulfils the minimum requirement for the operating system (iOS 13) and is therefore fully compatible.