Sony Xperia Z1s (C6916) owners have been patiently waiting for the handset to be rooted since it launched earlier this year. Normally achieving root is a relatively straight forward process if you can unlock the bootloader. The problem for Xperia Z1s owners is that this is a T-Mobile US carrier device and thus the bootloader cannot be unlocked.
Well, thanks to a root exploit discovered for the Sony Xperia Z2 and Xperia Z2 Tablet (note: full root has yet to be achieved for these models), XDA devs jcase and beaups have managed to fully root the Xperia Z1s.
This means that Xperia Z1s owners can finally use root apps and can also dabble in custom ROMs. However, it is worth noting that this root solution is specific to the current Xperia Z1s kernel, so users may not be able to use Android KitKat until a compatible kernel is provided. Full root instructions for the Xperia Z1s can be found here.
Hopefully the ability to achieve full root on the Xperia Z2 and Xperia Z2 Tablet with locked bootloaders will also be possible very shortly. We will keep you posted with any further developments.