According to Apple's developer page, 74 percent of Apple's mobile devices are running iOS 7. That means nearly three out of every four iPhone, iPod touch, and iPad device is equipped with the latest version of Apple's mobile OS. Another 22 percent are sticking it out with iOS 6, and only 4 percent are running an earlier version.
It's quite a different picture than Android. At present, 1.1 percent of Android devices are running the latest release, version 4.4 KitKat. To be fair, KitKat is fairly new, but even after a year and two months on the market, Jelly Bean (version 4.1.x - 4.3) is only found on 54.5 percent of Android devices. Another 18.6 percent are running Ice Cream Sandwich, followed by 24.1 percent using Gingerbread, 1.6 percent on Froyo, and 0.1 percent on Honeycomb.
We're not posting those figures to disparage Android. Even though users are spread out across various versions, the upside is far greater choice over devices. Android users also have an open playground to play in, with a robust community of modders and ROM developers. Most devices can be rooted and upgraded if you're willing to spend some time tinkering.
Still, there's an advantage to having users on the same page. Getting back to Apple, the penetration rate of iOS 7 is a motivating factor for developers trying to reach as many customers as possible. Since so many users are updated, an app developed and optimized for iOS 7 will have a potentially large audience to tap into.