Let's calculate how much data you use per month so you can choose the best cell phone plan for you.
On iPhone: First, go to Settings → Cellular. You'll need two numbers: Current Period GB (under the Cellular Data heading) and Last Reset Date (all the way at the bottom, under Reset Statistics).
1. How Much Data Have You Used In The Current Period?
Enter how many GB you've used in the Current Period.
Hint: You'll find this in Settings → Cellular on your iPhone.
2. When Did You Last Reset Statistics?
Choose the date you last reset statistics to calculate how much data you use per month.
Hint: You'll find this at the very bottom of Settings → Cellular on your iPhone.