Reduce the size of empty unity project android

Question

I am working on a android game project with unity engine (version 5.2.0f3). My question is: an empty compiled project is 18 Mb APK file size. Why and how can I reduce the size ?

Answer 1

The only thing you can do is Strip Byte Code, Use .NET 2.0 Subset, Set Script Optimization to "Fast but no exceptions", Vertex Compression to "Everything", and optimize mesh data.

In 5.3.2f1 it has more options, but in 5.2.0f3 I think it has a few of those mentioned above.

This is located under Player Settings, Other Settings, very bottom.