If you have an iPhone 4S or an iPad 2, you probably shouldn’t have upgraded to iOS 8. But in case you did and are stuck with subpar performance on your device, you should definitely install iOS 8.1.1 to at least get some marginal improvements on your older Apple devices. Ars Technica has done a thorough look at how iOS 8.1.1 performs on the iPhone 4S and iPad 2 and it says that while both devices do perform better with the newest update, some critical issues remain.
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