Idea, Airtel and Vodafone are likely to launch voice over LTE or VoLTE services this year in their efforts to compete with Jio. This will enable these telcos to keep their low-end subscribers from switching to Jio, which runs an all-VoLTE network and offers voice calls for free.
VoLTE allows an operator to give both voice and data, with voice being just another application that rides on an LTE data network. VoLTE technology gives voice in data format and can be delivered at a lower cost per minute than traditional voice calls. VoLTE-ready devices are expected to hit critical mass in the Indian market which is probably why Idea, Airtel and Vodafone want to start VoLTE services.