It's now easier than ever to keep an eye on how much data is used by Wi-Fi assist, thanks to a new data monitor found in iOS 9.3 beta 1. Wi-Fi assist, is the controversial feature that taps into your iPhone's cellular connection in those instances where the Wi-Fi connection may not be adequate enough.
First noted by MacRumors' Juli Clover, the addition of data usage numbers for Wi-Fi Assist will help those who claim to have experienced exorbitant amounts of cellular data usage due to the feature.