Xperia Z3 was the flagship device of second half of 2014. Xperia Z3 runs on a 2.5Ghz quad-core Qualcomm Snapdragon 801 processor, 3GB of RAM, 16GB internal storage and a 3100mAh battery. The 5.2″ IPS LCD display has a 1080p resolution and utilises Sony’s Triluminuous backlighting technology. The Xperia Z3 is also IP65 and IP68 compliant, meaning it’s good for those dusty or wet environments. Z3 also has a new impressive camera, featuring a 20.7MP.
Sony devices are yet to receive official Android Marshmallow support. However custom ROM developers are working on the same and they have come up with unofficial nightly of CM 13. This ROM will update Xperia Z3 to Android 6.0 Marshmallow. If you are interested, a detailed guide is given below.