This screenshot was leaked recently and is supposedly a screenshot of iOS 8. The screenshots shows the Healthbook app that Apple is rumoured to be working on which will sync data from the iWatch. Also shown are Preview, Text Edit and Tips.
Rumours suggest that Preview is likely to become a stand alone app in iOS 8 but there are mixed feelings as to why Apple would include Text Edit as Notes and Pages both achieve the same result and are free. iOS 8 is still in early development and a lot will change before public release. The Tips app is still a mystery.
Insiders close to 9to5Mac have verified the image as legitimate.