When jio released in the end of 2016 it provides free data netwok to its all user nearly about 6 month.then after that jio starts providing net on cheaper rate and slowly slowly it covers whole market in India.
there were certain difficulties for jio in starting. it was difficult to make call to another sim-card generally with airtel but later on the problem of calling was also solved by the jio .
the best part about jio sim card is that it provides network in many places where different sim card are not able to give network.
jio generally charge 399 for 3 months unlimited calling and data pack and 149 for one month .
in 2018 jio launched their phone also, which is not smart phone but then also net is working in it but the condition is jio sim card should be there.
as compare to mobile the demand of sim card is more in the market.
I m using jio sim card from 2016 for me it is the best sim card which is available in the market.