Originally Posted by ffp.
Hi, i just bought my Z1 and I might receive it next week. But i wanted to know if it si possible to flash kernels from recovery like samsung phones or if it still need a pc (flashtool or adb) like the 2011 xperias
You need PC. If the phone is with Android 4.2.2 you have first root you phone, backup up TA and DRM keys, then update to FTF .290 Android 4.3, Unlock Bootloadre and root again, install recovery or install custom kernel with recovery implemented.
Why all of this?
You need TA and DRM key in case you want go back to factory state and do not avoid warrany, DRM keys are lost when you unlock your bootloader.
Because to flash custom kernels you have to unlock your bootloader, if you unlock you bootloader you will broke your camera on Android 4.2.2.
With 4.3 you do not have this problem with the camera because the problem was fixed with the update.
If you want flash stock kernels you don't need to unlock bootloader but stock kernels are stock, no tweeks and no recovery.