The Android 4.4.2 build version I9505XXUFNA1, available for download for the GT-I9505 model of the Galaxy S4, is said to be relatively stable with few bugs. SamMobile shared Android 4.4 test firmware for the Samsung Galaxy S4 on Friday. Android 4.4 KitKat is making its first appearance on the standard Samsung Galaxy S4 in the form of leaked firmware.