
iOS 9 may run smoothly with all of its new features on Apple's latest devices, but the old and tired iPhone 4s hasn't exactly been known to run very well with the latest operating system from Apple. In fact, the operating system that is almost certainly designed to be used with larger display iPhones with their major hardware upgrades has not been very well optimized for the slower 32-bit dual-core A5 processor and the 3.5-inch display.
As a result, Apple is now facing a class action lawsuit regarding the matter since iPhone 4s users that have upgraded to iOS 9 are not happy with the performance and the losses in performance can actually impact day-by-day use of the device to the point where upgrading to a brand-new expensive iPhone may be the only answer to having a fully-functional iPhone that isn't laggy beyond belief.
Since Apple wasn't very straightforward at saying that iOS 9 would drastically ruin the performance of the iPhone 4s and because there's no way to downgrade to earlier firmwares that ran much easier on the device's hardware, the plaintiffs suggest that it was a malicious act by Apple and they should have to pay, rather than the plaintiffs having to purchase a new iPhone just to have fluidity back.
It's also noted that the "faster performance" advertised on Apple's Web site with iOS 9 is a bit of false advertising depending on the device you might be using, because although newer devices may perform better, the iPhone 4s is certainly seeing the opposite results.
Source: Apple Insider
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