In iOS 6, it shows you how much data you use, but it did not define or described what made up that number. To monitor and track your cellular data usage in iOS 7, first go into Settings. Have you ever wondered how much data you should get with your carrier? Do you barely use your data plan but pay for a huge one anyways? Or do you go over data each month with your data plan and have no idea why? New in the iOS 7 Settings application is the ability to track cellular data usage per each app you have installed on your device.