iOS updates: Why are some Apple products behind on updates?

A new study from mobile security vendor Zimperium Inc. showed that nearly a quarter of the iOS devices it scanned weren't running the latest version of the operating systems. If Apple controls iOS updates, and enterprise mobility management vendors can't block them, then why are so many devices running older versions? Are there other ways to block iOS updates?

Zimperium's study showed that more than 23% of the iOS devices it scanned weren't running the latest and greatest version of Apple's operating system. Even though Apple has a more streamlined method of updating its mobiles devices than its main competitor, Android, this is only because it controls both the hardware and the software -- Apple doesn't rely on disparate manufacturers to apply patches.

That being said, it came as a surprise to many that so many iOS devices weren't up to the bleeding-edge iOS; however, there are a few reasons why we're seeing almost a quarter of iOS devices being delinquent.

For starters, some people just don't want the new update when it becomes available. Even though iOS updates can be nagging, it's possible to delay them or have your device remind you to install it later. It would be interesting to know how many devices are only one update behind the latest update to see if people are holding off temporarily or indefinitely.

Another reason that devices might not be up to the latest version is that legacy devices may not support the newest update -- the newer releases of iOS aren't compatible with every device. This might be a small percentage of devices, but it's still part of the 23%.

Likewise, certain devices have been jailbroken, and thus could have issues receiving updates. These are possible issues that can add up to the 23% found by Zimperium, but there are some configuration and operational changes that might also cause a delayed update.

By default, automatic iOS updates are enabled, and that's a great way for Apple to continue pushing over 75% of its devices to run the latest software update. While you can have the automatic updates disabled on an iOS device and delete the update after it's been downloaded, there is probably only a small percentage of devices operating like this.

Also, there's most likely a small percentage of people that don't have their devices connected to Wi-Fi, which is often how the update is downloaded, if not via iTunes on a computer.

Lastly, if a device can't access apple.com, then it cannot receive the update. In the past, I've seen web filters block iPads from accessing apple.com to limit what could be downloaded from iTunes. With this filtering in place, you're also stopping the download of the latest iOS update.

When all of these small issues add up, you can understand the percentage of devices that aren't running the latest update. However, I'm still curious to see what the average patching cycle for devices is after an update is released, as it's possible that Zimperium's scan was in the middle of a release, which could have inflated the numbers a bit.

Either way, there will always be issues with patching systems, but as consumer devices go, Apple is doing a pretty good job of having its iOS devices updated in the field.

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