Open the Settings app
Tap Cellular or Mobile Data
Scroll to view current data usage
Check the Current Period section
Review data used by each app
Reset statistics to track usage from a specific date
Go to Settings
Tap Cellular or Mobile Data
Scroll to the bottom
Tap Reset Statistics
Check your carrier app for detailed usage
Use Low Data Mode to reduce usage
Go to Settings
Tap Cellular or Mobile Data
Tap Cellular Data Options
Turn on Low Data Mode