Google's Aurimas Lutikas, Software Engineer, in a blog post explained that the number of Chrome users running Ice Cream Sandwich has dropped by 30 percent and it is hard for the team to support an older Android version while also building new version for devices running updated Android.
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Lutikas said, "In the last year, we've seen the number of Chrome users running ICS drop by thirty percent. Developing new features on older phones has become increasingly challenging, and supporting ICS takes time away from building new experiences on the devices owned by the vast majority of our users."
To put some context, Google's latest Android version distribution numbers suggested that Android 4.0.x or Ice Cream Sandwich was running on just 5.9 percent of devices, dropping from 6.4 percent the previous month. It's a clear indicator that the usage of Android 4.0 Ice Cream Sandwich has dropped significantly.
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Lutikas also revealed that since 2012 when the Android Ice Cream Sandwich debuted there have been 24 Chrome releases while there have been also three new Android versions shipped - Jellybean, Kitkat and Lollipop.
Detailing a bit more on engineering of a Chrome version, the Chromium Projects page notes, "While the number of Ice Cream Sandwich devices is shrinking, supporting them in terms of engineering effort and technical complexity is increasingly difficult over time. Each new feature or web capability that's added to Chrome must be built and tested for ICS. Often workarounds and special cases have to be added specifically for ICS, and that adds code complexity, slows performance, and increases development time."
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It concludes, "The number of ICS devices is now sufficiently small that we can better serve our users by phasing out support for earlier devices and focusing on making Chrome better for the vast majority of users on more modern devices."
Last month, Google introduced a specific red flag on Chrome browser that warned users of websites that encourage the download of unwanted software.