iPhone 4S eating my data

Anything running in the background?
GPS or location based things?
What apps do you use?
How much usage do you do on cellular?
What's your plan?
How much data do you actually use?

Impossible to give an answer without details, OP.

 

I had the same problem last month and noticed that "use cellular data for" was switched on for (iCloud documents, iTunes, passbook updates, reading list) in General/Cellular and it was also switched on for (documents & data) in iCloud/Documents and Data. I also switched it off for (iTunes Match) in iTunes & app stores as I don't use that service!

Once I did this everything reverted back to normal.

It also helped when I spoke to my carrier and they pin pointed the time when the data was used up and it was the early hours of the morning when the above services run.

HTH

 

If you are using Apple Maps or Google Maps for GPS it will suck data because the maps are not stored on the phone. When flyover came out, I played with it for about an hour and consumed over 400MB.

 

Wow, 200mb for a full month.
That wont even last some people for a day.

 

Check out Onavo. It sends your data through their servers and then the Onavo app can give you a breakdown of where all of your data gets used.

 

Be careful with Onavo count it can use up some data.

 

What carrier do you have?

Is this a new issue, as in have you had the 4S for awhile or is this a new plan with a new phone?

I ask because I used significantly more data on AT&T per month than I do now with Verizon. I break maybe the 2 GB mark per month now with two iPhone 5's on Verizon. On AT&T each phone (I had two iPhone 4's) would use about 2 GB's for a total of 4 per month. Same amount for email, web surfing, streaming video and music so our habits haven't changed. Only difference is that we have LTE now versus just 3G.

I originally got us the 8 GB plan because I thought we would need it but dropped it down to 6 GB after the first few months. Figure that will give us plenty between the two phones and incase we want to share the connection with our two iPads.

 

Yes. I've used Onavo Extend in the past, which adds server-side compression to lower your data usage.

 

So it's AT&Ts fault you're using up your tiny data package fast
They should just not measure your data at all.

 

Any notification from apps or emails use data even when on WiFi. If you truly want to stop cellular data, you need to turn off cellular data in settings. The phone will always use some cellular data to maintain a connection. But seriously with a 200 MB data limit, you can only use about about 6.6 MB a day. You can update 2-3 apps on cellular data and be around 100 MB. With your data setup, you really should be on a dumbfound and use a iPod Touch or iPad on on WiFi. Just my opinion, so take it for what is worth.