My project content size like this,
In case of a large png files existed try to enable the AAPT and use the next:
android {
…
buildTypes {
release {
crunchPngs true // or false
}
}
}
There are 2 build variants, for Debug and for Release. Default build option is for Debug which makes size big.
Check this answer : How to use the ProGuard in Android Studio?
Clear the project and build again. Check raw, asset folder.
Give a look at this http://developer.android.com/tools/building/index.html .