How to use Reliance Jio 4G SIM in 3G Smart phone ? Are you sad that you can’t avail the bumper offers of Reliance Jio since you have 3G phone? Follow the steps given below and enjoy the Jio 4G freebies on your 3G phone. Remember that for the trick to work, you must have following in your 3G phone- Android 4.4kitkat or Mediatech chipset. – First you will have to download the MTK Engineering Mode app, for which you have to click here . – On this app you can run advance setup, which is available in MTK Phone Engineering Mode Menu. This is also called service mode. -Now open the app that you have installed and enter the mobile specific code of the engineering mode. -Then tap on the MTK settings and click on the preferred network option. – Then you have to choose a network mode from 4G LTE, WCDMA and GSM and save it.