Sony’s new home launcher for the Xperia Z3 sticks much more closely to Google’s stock launcher, than compared to the current version. You’ll immediately notice larger app icons, overall the launcher looks very similar to the Google Now Launcher. The Xperia Z3 home launcher has now been ported to older Xperia hardware running Android 4.2+.
If you want to try it for yourself, then the download links are below. There are two versions, the first should work on non-rooted handsets but may not fully support stock widgets, transparent system UI and navbar. The second should fully work but you will need to be rooted. Install like a normal APK, although make sure you wipe home data first.