1. To check and manage data usage, from the home screen, tap Settings.
   Note: To check your current month's data usage dial *data# (*3282#) on your mobile phone to receive a text message with the current bill cycle's usage.
   
2. Tap Cellular Data.
   
3. Scroll to view a list of apps and the amount of cellular data they have used.
   Note: The amount of data displayed is the amount used since the statistics were last reset. To reset the statistics, scroll to the bottom, then tap Reset Statistics.
   
4. To disable cellular data usage for an app, tap the Cellular data switch next to the app name.
   Note: Learn more from Apple support article: Learn about cellular data settings and usage on your iPhone