How to Check Data Usage on iPhone
Step 1. Unlock your iPhone and go to the home page. Look for the “Settings” application. It is the app with the grey icon.
Step 2. Open the application to go to the “Settings” page.
Step 3. On this page, look for the “Mobile Data” option and click on it.
Step 4. The new screen that appears will show everything you need to know about your data settings and usage.
Step 5. Scrolling through the page, you will see all the applications on your phone which are currently using data. The data used by each application will be mentioned below their names. You can individually switch off data usage for the applications you do not want running.
Step 6. In case you want to view a summary of your data usage, click on the ‘System Services’ heading on the same page. You will have to scroll through the application list to find it.
Step 7. The new screen that comes up will carry the entire summary of your data usage, organised by applications.