I have the Samsung Galaxy S4 - the systemui was not working so I looked online and started to follow the instructions. The first instruction was to power off the device and then hold volume up and power to bring up the recovery page. I first got a warning saying that 1 wrong swipe could wipe my phone did I want to continue. I said yes then I had the screen I said previously. I think my phone was updating but the systemui is still not working.