Following the launch of iOS 8 back in September, many iPhone 4s users reported widespread issues ranging from slow performance to choppy animations. With Monday's release of iOS 8.1.1 promising "increased stability and performance improvements for iPad 2 and iPhone 4S", Ars Technica has now put those claims to the test.
iOS 8.1.1 improves performance in a few specific places, ones that may well be important to heavy users. However, it doesn't improve responsiveness or consistency, two of the problems you'll notice the most if you upgrade from iOS 7. Let's look at the short list of things you can expect to improve if you're using an older iDevice and the longer list of things that won't.
In its study, Ars Technica found launch times of system apps like Safari, Camera, and Messages essentially unchanged from iOS 8.0 for users with Apple's A5-based phones and tablets. The one exception was Safari, which saw a minor improvement compared to iOS 8.0, but all system apps still took considerably longer to launch on iOS 8.1.1 than on iOS 7.1.2. Interface lag such as for bringing up the keyboard or Control Center also remains an issue for these devices under iOS 8.1.1
The one bright spot Ars ran into was, surprisingly, in long-term speed and stability. Under certain circumstances, iOS 8.1.1 was found to in fact improve stability and performance despite the confines of 512MB of RAM on these devices. Tests involved loading up multiple memory-intensive tabs in Safari and then using multitasking to switch away from and then back to Safari to measure reloading times.
It's hard to say exactly what Apple has done to improve performance under these RAM-starved conditions, at least not without more input from Apple (the company has declined to comment for this story). We also can't list exactly when users can expect to see improvements, beyond the "play around in other apps and then jump back to Safari" test we've engineered here.
The best we can say is that something about the process of loading and ejecting processes to and from the A5's 512MB of RAM could cause slowness and instability in iOS 8.1, and whatever the problem was has been at least partially addressed in iOS 8.1.1.
Overall, improvements for A5-based devices under iOS 8.1.1 are minor, as has been shown in other testing, although some will appreciate the improved multitasking performance with Safari. As Ars notes, iOS 8.1.1 isn't exactly the vast improvement for the iPhone 4s that iOS 7.1 was for the iPhone 4, but it does offer nominal improvements to the overall experience without making other areas worse.
Apple's A5 devices are definitely showing their age, although they do remain on the market with the original iPad Mini and iPhone 4s being sold as low-end options and the fifth-generation iPod touch still being the current model of that device. The spread between these A5 devices and Apple's latest A8-based iPhone 6 and iPad Air 2 models is indeed significant, and it is clearly posing challenges for Apple and developers alike to continue adequately supporting these low-end devices.