Google launched Android in 2008 on a single phone, but the platform was designed to be adaptable and freely available. Anyone can download the open source code and make changes to it. This has led to massive success for Android, which is now the most popular computing platform on the planet. At the same time, Google’s open approach has contributed to the development of a fractured user base. The problem only seems to be getting worse as time goes on, too. As of the most recent platform status update, there are around 1 billion Android devices out there running software more than two years out of date.

The Android platform versions report is updated almost every month, and all the details are posted publicly on the Android Developer website. The estimate of 1 billion “old” devices comes from hardware engineer Dan Luu, who used the rough numbers of active devices from Google to figure out how many Android phones and tablets out there are running ancient versions of the software. As recently as May 2017, Google says it crossed 2 billion active global devices. Today, around half of all devices are running Android 5.1 Lollipop and earlier. That version was launched in early 2015.

Luu notes that the adoption rate for new versions of Android has been slowing. Last year, Nougat’s growth tracked several months behind Marshmallow the year before. As of the new report, Oreo is on the same trajectory as Nougat. There are several likely mechanisms for this trend, including the fact that many OEMs are slow to get updates out the door. However, device makers have strived to improve this in recent years. Most phones take several months to see a new update, but that’s better than it once was. So, why are new versions getting a smaller share?

Despite some design changes that make phones more disposable (hello, non-removable batteries), hardware today is vastly more reliable than it used to be. If you want to use a phone for three or four years, you might be able to do that. Thus, some people are probably just holding onto their phones longer. There’s also the trend of increasingly inexpensive hardware. There are huge numbers of super-budget Android phones sold on prepaid carriers running Lollipop and even KitKat, and they’ll never get updates. In many cases, silicon vendors don’t even have driver binaries for newer versions of Android, which isn’t actually Google’s fault. These phones were produced years ago, but people are still buying them as cheap burners.

This is a problem not only because these phones lack modern features for app developers. They’re also insecure by today’s standards. After a few years without security patches, your phone could be exploited simply by visiting the wrong website.

Google isn’t standing idly by, though. In Android 8.0 Oreo, it added a feature called Project Treble. Devices that ship on Oreo have modular system images that make updates easier and more cost-effective. Of course, that requires device makers to actually care about updates. The people selling you a $99 phone probably never will.

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