If I come across an app that measures other app's data use, I'll post again but I fear this would cause some loss of battery time.
My iphone has wi-fi 24/7, yet my data usage is over the limit. Where can I find a listing of which iphone apps use data and not wi-fi? Thanks for your help.
I have the same problem and found two things that help:
1. Turn off cellular data until you actually need it for anything. There are a few apps (like visual voicemail) that need it, but it's easy enough to turn it back on for those occasions.
2. Leave your phone/iPad plugged in, esp. at night. Carriers send all kinds of data around then. If plugged in, it should use WiFi instead as I've been told.
3. Get Dataman Pro or some other app that can tell you which apps are actually using data and when. I find that the New York Times app uses my data for example when I don't even have it launched.
4. Look in your settings for notifications and turn off ones you don't need. Ditto for location services.
With these tips, I've been able to keep my data usage under 200MB/month.
Hoarding photos on your phone?
Those picture are hogging memory and could be slowing down your phone.