Apple today updated its iOS adoption numbers to show that iOS 9 has finally hit the 75 percent mark. In other words, the latest version of the company’s mobile operating system is now on three out of every four of its devices.

iOS 9 share (which includes iOS 9.1 and iOS 9.2) has taken less than four months to reach the three-quarters mark, an impressive feat. This is much faster than iOS 8, which took six months to hit the same adoption milestone.

These latest figures come from the usage of the company’s App Store, presented on the support page for developers. Apple updates these numbers regularly to give app and game makers a good idea of which features they can leverage to how many users:

ios_9_adoption_january_12_2016

iOS 9’s quick rise means iOS 8 is now on less than a fifth of devices (19 percent exactly). Earlier versions are in the single digits, at 7 percent. As we’ve noted in the past, there is a discrepancy in Apple’s charts: The numbers sometimes add up to 101 percent.

When iOS 9 passed the 50 percent mark, Apple declared it the “fastest iOS adoption ever.” That likely remains true today, though we’re not expecting a press release from Apple on the topic.

Because iOS 8 saw a much slower adoption rate compared to iOS 7 and iOS 6, it’s no surprise Apple is touting iOS 9’s gains. Aside from being wary of bugs and not being impressed with the feature set, the size of the update itself (grabbing it over the air requires about 5GB of free space on your device) was the big sticking point. Apple cut down the update size of iOS 9 to around 1.3GB, less than a third of what it asked users to download when moving to iOS 8.

At the end of the day, the result is developers will be more likely to use iOS 9-specific features. This in turn only encourages more users to upgrade as they seek to get new apps and new features in existing apps.

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