It may not be possible to provide a clear idea about the quality of a prepaid telecom service in Mumbai or any other region for that matter. You may not get a clear idea of how does the network perform in your area. I would advice you to opt for trial plans - if any of the telecom operators allow in your location. The best friends in this case to suggest a better SIM card are your acquaintances and friends in that particular area.
Here is a comparison of 4G networks in India.
1. Reliance Jio
It offers 4G connectivity in almost all the cities and states across India. It may be reminded that it was Reliance that revolutionised the concept of prepaid and began a tariff war.
AirTel was the first telecom to launch 4G services in India. It could be a best choice as it provides a nationwide coverage.
The so called World's best 4G telecom provider started its 4G services in 2016. They have licences for band 40 and band 3 ony. Vodafone Supernet has service available in almost all states except AP, TN, WB, Assam, Bihar, J&K, North East India, Orissa.
This is the latest entrant in the 4G band wagon. It has only Band 3. They are yet to make a mark in the 4G space. Idea cellular has operations across all states except Delhi, Rajasthan and Bihar.
As far as Mumbai is concerned, it appears as if AirTel is the best among the competitors. Repeated speed tests have indicated that AirTel has kept its promise of 4G challenge. It offers you a speed of at least 30 MBps.
On the other hand, Vodafone does not offer better peak hour speeds. It has been observed that the speeds struggle to move beyond 10 mbps. The low speeds can be due to 1800MHz spectrum that Vodafone has got in Mumbai.
For Tariff plans, you may visit the official website of AirTel and Vodafone. Reliance Jio can also be a good option in Mumbai. I would advice you to test different operators in your area by opting for trial packs and check the service quality in your area.
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