This is my first post on this forum. So please do not murder me if I mess up 
Basically it tracks your data usage right on your phone. You do not need to login and fetch your stats from your carrier.
http://slickdeals.net/f/5216474-DataMan-iOS-app-Real-Time-Data-Usage-Free-Reg-99
I think this app is cool and those who do not have unlimited data may benefit from it. I myself have sprint (sigh) with unlimited data. But still snagged it to get a sense how much I am using so I will know what data plan to shoot for if/when I switch carrier.
Basically it tracks your data usage right on your phone. You do not need to login and fetch your stats from your carrier.
http://slickdeals.net/f/5216474-DataMan-iOS-app-Real-Time-Data-Usage-Free-Reg-99
I think this app is cool and those who do not have unlimited data may benefit from it. I myself have sprint (sigh) with unlimited data. But still snagged it to get a sense how much I am using so I will know what data plan to shoot for if/when I switch carrier.