If you are a client of Karbonn mobile and have brought the model of Karbonn A9+, A15, A21 or A30 Smartphone will be getting free 500 MB free 2G/3G data usage from the Bharti Airtel for six months. Now both Karbonn and Airtel linked up with each other to promote their business together by providing an attracting skims with the handset. Suppose you like to access free 500 MB data usage simply buy Karbonn...