Unity 2017.1.03f3 Bad icon quality on android

I'm building an app for android and its icon always looks very blurry when I install it on device. The icon itself is a PNG file 512x512 which is very sharp by itself. It also looks sharp when I add it to player settings in Unity. But after I build it and install on my phone or to BlueStacks emulator it looks terrible while the icons of some other apps looks very nice and sharp. I've googled a lot of topics with the same problem, but their solutions are way too outdated already because they all advice to set icon as GUITexture (which is not present anymore) to avoid converting it to POT texture. So my question is how can I make my icon look sharp in new Unity? What am I missing?