I have been using Reliance Jio for one month now. If you have your Adhaar Card and you have done the online registration of the sim by going to the website and scanning the bar code, you don't even need to stand in line to get the sim.
It will fit in the 4G sim slot of your phone. At starting it was giving me the speed of 10Mbps but now since the users have been increased its still giving me 3Mbps, which I don't think so is bad because it's absolutely free.
The internet and the wifi works good enough to do your browsing including some of your online work.
I would definetely recommend it to everyone. People are there who are spreading wrong surprised about it but it's not true.
Ambani has done a real good job.