My device is Galaxy Tab 3 7.0 At&t, and it is rooted via Kingo root program. I tried to flash a custom rom to my tablet, but when I googled about flashing a custom rom, I needed to unlock my bootloader first. I did search about how to unlock my bootloader, but none of them were Galaxy tab 3 specific. I'm not very good at these things and I need help from more experienced users. Please help.