Last Updated on August 14, 2023 by HBW2
Before you are going to take any inference, first you need to ascertain the location where you are judging any network. Because the network quality is very much dependent on location. The prominent cellular networks in India are Jio, Airtel, VI and BSNL. Here a comparative discussion done mainly on the basis of location and customer services.

All across India (Including Jammu, Kashmir) Jio has the best 4G availability and consistent 4G Speeds. Airtel is better than Jio when it comes to cramped localities (i.e. places with densely packed multi-storey buildings)Jio has better coverage in both skyscrapers and remote villages.
If you are a foreigner reading this, buy Airtel SIM first as they have best onboarding policy for foreigners with instant activation. Once you get your airtel SIM, you may choose to buy a Jio SIM. (Jio has frequent verification issues with foreigners’ documents and poor customer support)
Your best choice as travelers are Jio and Airtel (both if possible) as they both have VoLTE & VoWiFi — even if you are moving out of India.
The 5G speed of Jio’s averaged at 506 Mbps, Airtel was at 268 Mbps according to the February 28, 2023 report of Ookla, the global leader in network intelligence and connectivity insights.
Only if you have a number which you want to preserve, and do not use it for regular calling/internet, use BSNL as it has the cheapest validity plans. It is sometimes slow to receive OTPs too — so do not use it as your banking SIM as well.
Your phone will last longer if you choose the network with the best signal strength. Airtel 4G is better as it does the least network switching.

As per an independent survey the customer care service of Airtel is far better than jio. It is due to the fact Airtel has been longer in this game than the jio. Jio is only 4 year old company while Airtel is a three decade old company. Jio has started fibre services only 2 years back. The commercial roll out of fibre services was only one year ago. So there is lot to be put in places to create a proper infrastructure to address all the customer grievances. Hence there is customer care services are are not as good as Airtel but they are improving.