The shortcut menu (quick ball) provides a quick icon on the side of your redmi devices which helps to reach apps instantly. It looks as shown below in the image
Well as we recently had an update for both the devices as miui 188.8.131.52 which introduced Android Lollipop in redmi2 prime but for redmi2, the android version still remains KitKat. But both the devices got an option of adding shortcut menu. So follow the easy steps of how to add this menu to your devices.
1) First of all, go to the settings of your phone and click on additional settings.
2) In additional settings, find the option of ‘Shortcut Menu.’
3) Click on the shortcut menu and enable the option of shortcut menu.
That’s it. Your shortcut menu will be enabled and from there, you can just reduce the usage of your normal navigation buttons or even add shortcut to your favourite apps. Hope it helped! 🙂