Sony's update to the Z3, the Z4 brings some hardware updates to their 2014 phone:
Sony Xperia Z4 official: 5.2-inch FHD display, Snapdragon 810, 3GB RAM and 20.7MP camera | Android Central
To compare them with each other, Alex wrote up a comparison article:
Quick comparison: Sony Xperia Z4 versus Xperia Z3 | Android Central
I think aside from the battery, it's not that bad. Even then, the battery only went down by 170 mAh.
Sony Xperia Z4 official: 5.2-inch FHD display, Snapdragon 810, 3GB RAM and 20.7MP camera | Android Central
To compare them with each other, Alex wrote up a comparison article:
Quick comparison: Sony Xperia Z4 versus Xperia Z3 | Android Central
I think aside from the battery, it's not that bad. Even then, the battery only went down by 170 mAh.