Sony did not declare its Xperia Z4 smartphone at MWC likely because it was not prepared in time for the show. However, the company is unquestionably working on the successor to Xperia Z3 and these alleged leaked pictures of the Z4 metal framework could be the evidence of this.
In the pictures, there is a comparison of Z3 and Z4 metal frames. The Z4 frame is 1mm thinner than its predecessor.
Another change, which we noticed earlier on the announcement of Xperia M4 Aqua and Z4 Tablet – the flap covering the microUSB to prevent the water damage, has been removed on Z4 too. The dock port on the side, which we have seen earlier on Z series device, is no more available on Z4.
Besides that, there are no notable differences between Xperia Z4 and Z3. We anticipate the remaining changes to be with a greater resolution screen and quicker central processing unit over the Z3. We’ll need to wait and see what Sony has in store for us.