What are you mean by that? This game is not released yet, and it's unlikely that it will happen in the near future. APK is a not official(pirate) way to install applications. On this platform you can't install a paid application for free beacause it will be piracy! They are too lazy to make it free? It's simply not profitable for them to give it away for free, especially since it's paid on all other platforms!

from where did you get the apk ?