Why can't I disable cellular usage for an individual app on iOS 7?
I had the same problem and the above fixes didn't help either. What ended up working was turning off the apps I wanted off, and then turning off cellular data altogether. Then moved back out of Cellular to the main Settings menu, then back to Cellular and my apps were still off. Then switched cellular data back on and the apps I wanted off stayed off. I also tried deleting and re-adding the offending apps and that worked too.