title: How to get the connection interval between peripheral (BLE device) and central (iPhone)
body: <p>I am working on a BLE project and the peripheral is a BLE device and central is an iPhone (iOS-10.3.1). I read quite a few posts, they all mentioned that the minimum connection interval for iPhone is 30ms. However, I just wonder, is that possible to get the "connection interval" in the app programmatically? My development environment is XCode8.3.2 + Swift3.1. The BLE device uses nRF51 chip. I will be really grateful if you could post some code or direct me to the right method that I should look into. Thanks</p>