I bought tata docomo simply card. After watching there advertisement in which they claim. They have their cellular tower range to all over in India. But when started using tata docomo sim. I was struggling to get the signal in my bedroom.
Every time I had to go out at the balcony to get better signal. Even in balcony I hardly was getting 1 bar of signal. Call quality was so bad on thier network. And Internet doesn't work most of time when I get full signal strength. They have very bad cellular network. Please stay away from Tata docomo.