Big scene weight in apk

All scenes in windows folder weight 6 mb.
After building a project, scenes weight 117 mb in apk file. Why scenes weight increased so much?
How to decrease it?
From 6 to 117 mb?100303-bandicam-2017-08-18-22-56-26-378.jpg

Solution:
Edit-Project Settings-Quality
Decrease quality. In my case it was “Fantastic”, so unity added a lot of additional files into scenes. When I changed it to “Simple”, my scene weight in apk decreased to normal size.