How to disable data usage on an iPhone 5?

And is a data plan required
I have AT&T
Do any other iPhones have this feature

Yes a data plan is required. But you can turn off data by settings>general>cellular then choose to turn off just 4g or all data together

Settings - General - Cellular - Turn Cellular Data OFF

This will disable all cellular data on your iPhone, but a data plan with the iPhone IS required, so you will still be charged for it.

Yes, you can turn off data but data plan is mandatory for all smartphones and especially iPhone. So there's no way to avoid data plan. All the other iPhones have this feature.

  • Unknown data usage on iPhone 4S? My family and I all have smartphones (all iPhones except one) and on our phone bill, it says that we're already at 6.7 GB, in 15 days… Looking further into it, I noticed that on each phone, data was being used every hour. Like anywhere between 1 and 19, 000 KB being used exactly every hour. Like 3 KB at 1:49, 15 KB at 2:49, 7 KB at 3:49 in the morning. KB's aren't a lot, but when you have 6 devices using KB's every hour, it really adds up.
  • Under settings on my iPhone, does the data usage include Wi-Fi usage? Because its stating a ridiculous amount and I've had my data off… And my Wi-Fi on. Does the total of data include the amount of Internet I'm using when on Wi-Fi? I'm so confused
  • IPhone: settings cell usage vs AT&T's data usage number? AT&T has a number, by calling it will send you a text message telling you how much usage you have used on your data. But also in the iPhone there's a cellular usage count in the settings app which also tells how much data you have used. Both of my cellular usage counts are different. Which is right?
  • IPhone 5 data usage. How much data will I need for certain apps? If I'm sending around 15-20 tweets a day, refreshing my twitter feed frequently about once every 10-15 mins & refreshing an Instagram feed around once an hour will 250MB's data be enough for a month? I won't be posting any photo's on Instagram or Twitter when I'm away from Wi-Fi. I'll also be receiving about about 10 emails a day without attachments?