When Apple first released iOS 8 to the general public, more than a few people with older devices such as the iPhone 4S, iPad 2, and iPad mini noticed that it slowed their devices down to a crawl.
When Apple released iOS 8.1.1, they promised that the update would fix some of the speed issues that iOS 8 had on older devices.
So how’d it work out? iOS 8.1.1 is sometimes an improvement. Sometimes, but not always. And even then, it’s not a huge leap.