iOS 9.2.1 makes speed boosts for users with Apple's older iPhone 4s and 5

The iOS 9.2.1 update can potentially make iOS 9 a smoother experience for people with older iPhones, according to a new series of YouTube videos featuring side-by-side comparisons with devices running iOS 8.4.1.

Although installing 9.2.1 still causes an iPhone 4S or 5 to boot slower, once in action the software can load apps as fast or faster than 8.4.1 in many circumstances, according to iAppleBytes. Boot times are said to be speedier than 8.4.1 when running the software on an iPhone 5s, which was also the first iPhone with a 64-bit processor.

A consistent problem with iOS has been the tendency for devices as little as a year or two old to suddenly see slowdowns after upgrading to a new version. This is despite the fact that Apple will deliberately disable some processor-intensive features on older hardware.

A lawsuit filed last month accuses Apple of misleading customers with the claim that iOS 9 is compatible with devices ranging back to the iPhone 4S. In reality Apple is practicing planned obsolescence, the case charges, since people who update a 4S will take a performance hit but find themselves unable to downgrade to 8.4.1 or earlier — nudging them towards buying newer hardware.

Apple was faced with a similar lawsuit in 2011, claiming that iOS 4 rendered the iPhone 3G slow and crash-prone. That case was ultimately tossed, but complaints about other Apple products have continued, and updates like 9.2.1 may be an admission that backwards compatibility needs improvement.