Apple just posted iOS 8.1.1 - a minor update to address stability and performance issues with iOS 8 on the iPhone 4S and iPad 2. It'll be a welcomed update because iOS 8 does feel a little sluggish on the iPhone 4S. Not sure if it helps other iDevices but no harm updating. Besides it's 43 MB in size. Do make sure you back up your iPhone or iPad before updating.