It must be nothing new for smartphone users to happily surf the web, upload pictures on Facebook, Tweet, download apps, stream video on Youtube and the like. What really comes as a shocker is the data bill charged to your account by the service provider after all that friendly fun. Well, your solution lies here in the form of Watchdog 3G. This is probably the most comprehensive data plan manager till date. Developed by Richard Gruet, the developer has done a commendable job with this app and has really helped heavy data users to keep a check on their data traffic. I for myself am a heavy user of this app on my Android.