Earlier this week at Apple's(s aapl) WorldWide Developer Conference, Tim Cook pointed out that the Android community can't get its act together when it comes to software versions. He's right that there are several editions of Android on phones around the world although I'd argue it doesn't matter quite as much since Google(s goog) is upgrading its services across all of those versions of late. Besides, the KitKat upgrade train is coming on strong, up more than 25 percentage points in North America in the past three months.

The data comes from Chitika's ad network where it last reported Android 4.4 adoption in April. At that time, only 10 percent of the phones browsing sites on its network in the U.S. and Canada ran KitKit. Fast forward to the current day and that figure is 37 percent, making KitKat usage second in North America only to Jelly Bean, the prior version of Android.

Android adoption North America June 2014
Unsurprisingly, Samsung accounts for the most KitKat users in the study overall; it sells the most handsets (by far) so even though it's typically not the first hardware partner offering software upgrades its phones, it makes up the difference in sheer breadth of market.

Google's own phones rule the roost when it comes to fast upgrades, which is one of the key benefits to owning a Nexus phone. But a very near second is owning a Motorola handset because it has quickly offered Android upgrades since launching its Moto X last August. That phone, along with the Moto G and E models is now getting Android 4.4.3, just days after Google made the code available to its partners.

android upgrades by manufacturer June 2014

Google first introduced Android 4.4 KitKat in October and although it can run on a wider range of phones -- the software is optimized to run better on lesser hardware -- it's still up to Google's hardware partners to make it available. For companies that have added their own software layer on top of Android, it takes time and effort to do so. Motorola is quicker than most partly because it has no such user interface skin, instead opting for a more pure Android experience with some added software features.

As always Chitika's data provides a proxy view of the overall Android market; if an Android phone never hits a website using Chitika ads, it can't be counted in the study. So consider it a subset of the whole market to give an idea of Android's current state in North America.