To enable VoWiFi calling on your Realme X for Jio and Airtel SIM, install the February 2020 security update version A.12. So, first, check for the update RMX1901EX_11_A.12 by going to the System update menu and then follow the below steps to enable VoWiFi on Realme X.
Install software update version A.12 on Realme XConnect the phone to a Wi-Fi networkGo to Settings > tap on SIM Card & Mobile Data > tap on Jio or Airtel SIM (SIM 1/SIM 2)Tap on Wi-Fi calling > and turn on the toggle.
Now onwards, your phone will route all your calls via the WiFi network or your Jio/Airtel network, depending on which signal is strong. FYI, the RMX1901EX_11_A.12 update isn’t the Realme UI (Android 10) update for Realme X. It is the ColorOS 6.0 update, but it is also the pre-requisite update for Realme UI. All users are recommending updating their Realme X to this version. Along with the February security patch, the RMX1901EX_11_A.12 update installs some third-party apps to latest version. Also, it fixes some known bugs, and improved system stability.
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