I'm trying to use ROM Manager app to backup the current ROM of my Xperia Z but it seems that cannot be done without unlocking the bootloader/ installing ClockWorkMod Recovery.
Is there any alternative for me to backup current ROM and flash another ROM without having to mess with bootloader or ClockWordMod Recovery?
Note that my device is already rooted using this method.
According to Sony's website, messing with the bootloader is likely to void warranty which defeats my purpose and so all my attempts to backup the stock ROM here.