If you are one of the lucky few who has managed to wangle an unlimited data plan, then you can move on (or send this link to a friend who isn't quite so lucky.)
For the rest of us, though, who have to ration out our Facebook/Twitter/YouTube usage in order to stay under our data cap, this is going to prove invaluable.
My Data Manager, from Mobidia, lets users analyse how much of your data is being used by which apps, meaning you can keep an eye on the worst offenders, shut them down, or just uninstall them altogether.
It allows you to track data usage over the last month, week, day and even hour, and even breaks it down into data used when connected to the mobile network, Wi-Fi or even (the horror) when roaming. We've had a go at it and it was enlightening (read: shocking and infuriating) to see which apps have been operating in the background, quietly churning away at our data allowance without us knowing.
My Data Manager is a free app, and can be found on Google Play and iTunes.
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