"Android (operating system): How can I solve ""Unfortunately System UI has stopped"" and ""Unfortunately Gallery has stopped"" messages on a Samsung S4 after I upgraded from Android 4.4.2 to 5.0.1?"
I have a Lollipop 5.0.1. How can I downgrade to KitKat4.4.2 in Samsung Galaxy S4 i9500 without rooting it?