How to get data consumption of individual iOS application (i.e. if a device has 10 applications which consumes data, I want to know how much data each application consumes)Answer1:
Short answer: you can't.
Long answer: all iOS applications are executed in a <a href="https://developer.apple.com/app-sandboxing/" rel="nofollow">sandboxed</a> environment, limiting the access that you have to data from another applications to avoid malicious behavior. The only way that you could obtain this information is if iOS had a public API that provided that information (it doesn't) or if the other applications published their information somewhere reachable from your application.