iOS 9 was released just over three weeks ago and in that time period the adoption rate of the latest mobile operating system has hit 57% of iOS devices, according to App Store usage as of October 5, says Apple.

Shortly after the release of iOS 9, Apple said the update was already installed on 50% of devices, which took only three days to accomplish, making it the fastest software release in the company’s history.

iOS 9 contains features to allow future updates to be installed automatically while you’re asleep, plus the ability to temporarily delete and reinstall apps to make space for updates.