Last year, it took 30 days of iOS 6 to reach a record 61% penetration.
By contrast, Windows 7 is still at less than 50% four years after Microsoft (MSFT) shipped it, according to NetApplications. That's because Windows 7 is still competing with Windows XP, a 12-year-old operating system that runs more that 30% of the world's PCs.
Apple hasn't said how many of the 700 million iOS devices it has sold since 2007 are still in operation, but Mixpanel's chart suggests that on Sept. 23, when Tim Cook announced that iOS 7 downloads had passed 200 million, the number of active iOS devices was roughly 350 million.
That means that as of Monday, 250 million were running iOS 7.
Dueling reports Monday on how much better the high-end model is doing than the low.
FORTUNE -- When the iPhone 5S and 5C went on sale last month, there was every reason to suspect that the more advanced 5S would draw more early adopters to the Apple (AAPL) stores than the 5C. And indeed, by one launch-day line count, the iPhone 5S buyers outnumbered 5C buyers that first day by 20 MOREPhilip Elmer-DeWitt - Oct 14, 2013 8:40 AM ET
Did a 1.3GB file downloaded 6.3 million times per hour push Internet traffic to 112%?
FORTUNE -- The mobile analytics firm Mixpanel has posted a cool little widget that lets you track the rate at which Apple's (AAPL) mobile customers are switching from iOS 6 to iOS 7.
Here's what it tells us:
As of 1 p.m. Eastern Wednesday, when Apple released its new operating system, the previous version was running on 93% MOREPhilip Elmer-DeWitt - Sep 19, 2013 8:23 AM ET
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