VoLTE (4G) Mobile Phones
Short Answer - See the list of VOLTE supported phones here.
There are over 300 phones of various brands listed. It is surprising that iPhone7 and Google Pixel supports only VoLTE Voice calls but not VoLTE Video Calls which are superior from 3G video calls.
Reliance Jio does not require 2G and 3G support on your mobile phone. It requires only 4G feature of your mobile phone.
If you phone as only 4G, you can use only Data.
If you phone as VoLTE and you will be able to make voice calls as well. For making VoLTE video-calls, you need newer mobiles with latest Snapdragon/Mediatek chipsets, such as Snapdragon 430 or higher.
Jio VoLTE Supported Bands
Communication happens at a certain frequency at which the mobile phone antenna sends signals. And the wide range of frequencies (spectrum bandwidth) is shared across multiple operators. Reliance Jio has license to operate their 4G network on three frequency bands listed below.
- FDD-LTE 1800MHz - also knows as Band 3
- FDD-LTE 850MHz - a.k.a. Band 5
- TDD-LTE 2300MHz - aka Band 40
Jio has India-wide license to use Band 5 (850MHz) and Band 40 (2300 MHz). 1800MHz spectrum of Jio is limited to all states of India except Jammu & Kashmir, Punjab and Utter Pradesh (West). Jio has 1800MHz operating on Utter Pradesh East circle.
When you look at the specifications of your phone, they specify which all bands your phone can operate 4G. Below is the criteria witch which you can make an informed and intelligent decision when you go with Jio.
Your phone must be capable of operating 4G in at least two of the three bands - Band 3, Band 5 and Band 40.
Band 40 provides very good, but due to the high frequency, the signals would find it difficult to reach interiors of your home.
Band 4 (850MHz) addresses the concerns that Band 40 brings. That is, when you are indoor, and if the signal strength of Band 40 is weak, you phone would automatically switch to Band 4, if your phone supports band-4.
Your phone might have several versions released in different countries. So, carefully find out the model number of your phone and google for "phone-name specifications". You can find a gsmarena listing and find the 4G bands supported in your new phone.
Which phone to buy to use Jio VoLTE?
Jio has published a list and you can view the list here - http://bit.ly/JioVoLTE
As you can see, there are 311 phones published of which few of the phones are yet to be released in India (as of January 2017).
You can search and buy some of them at Amazon or flipkart. Xiaomi Redmi Note 3, Redmi 3S Prime and Lenovo K6 Power are some good phones with VOLTE VIDEO CALLS ENABLED.