Sony Xperia ZX Premium with real 4k screen enabled, 3rd party phone dialer works

From xda-developers.com: Finally found the way to work fully for 3rd party dialer. This document shows you how to replace the built in phone dialer with a 3rd party phone dialer, so you can use the Sony Xperia ZX Premium in 4k all the time AND use it as a mobile phone, too :-)