India added 7.96 million active mobile connections in October 2017, with Airtel, Idea, Reliance Jio and Vodafone accounting for 77% of total active mobile connections in India, according to data released by TRAI.  
The Active connection data represents peak VLR (Visitor Location Register) data for the month. Some stats:
– There were 1,025.7 million active connections in the month of October 2017.
– Strangely, Idea has 102.83% of connections active on its network – the highest among all telcos. TRAI says the percentage of active connections is more than 100% due to in-roamers i.e. subscribers from other operators roaming in Idea’s network.
– Airtel has the second highest active connection base of 98.09%, followed by Vodafone at 94.11%.

In terms of the number of active connections, Airtel leads with 279.75 million connections followed by Idea at 196.27 million connections.
Mobile Operator Leaderboard For October 2017 (Total Connections):
– Reliance Jio added 7.3 million connections, taking its connection base to 145.96 million.
– Airtel added 3 million connections, taking its connection base to 285 million.
– Vodafone added 0.87 million connections, taking its connection base to 208.3 million.
Statewise data
– In terms of active connections, Maharashtra leads with 98.85% active connections, followed by Madhya Pradesh, Bihar and Kerala. Himachal Pradesh has just 79.11% active connections, the lowest among all circles.
– UP (East) has the most number of connections, with 104.2 million connections (104,203,535 connections). Maharashtra is second with 94.2 million connections (94,230,979 connections) and Tamil Nadu is third with 90.54 million connections (90,549,905 connections).
– Bharti Airtel holds the maximum percentage market share of wireless connections at 24%, followed by Vodafone at 18%, Idea at 16%, Reliance Jio at 12% and BSNL at 9%.
Top 4 telcos now have 77% of total active connections
The top three telecom operators in India – Vodafone, Airtel and Idea Cellular – added 5.95 million active connections in October 2017, accounting for 66% of active connections. Along with Jio, the top four now account for 77% of active connections.