Apple tracks the rate of iOS 8 adoption based on devices accessing the App Store with the current data being captured on January 5th, 2015.
The new iOS 8 adoption percentage jumps 8 points since late November when Apple reported that 60% of devices were using iOS 8 with incremental jumps between then and now.
Unsurprisingly, older iOS versions saw respective shares decrease over the same time period, with iOS 7 decreasing from 35 percent to 29 percent, and iOS 6 or below moving from 5 percent down to 4 percent of App Store registrants. The consistently rising share of iOS 8 users suggest new device sales are moving the needle helped along by a trickle of late upgraders.