Huge APK size.. is it normal?

Hi, I just finished my Android app. The VS2012 solution contains a PCL, a WP8 app and the Android app. The PCL is added as a reference to the Android project. Xamarin Android 4.10.01073.

I'm using the following components: Google Analytics, Google Play Services (Gingerbread), Reactive Extensions (Rx) for Xamarin. In the app i'm using Google Maps & Admob from Play Services.

The APK is huge (16,2MB), I noticed that the biggest assemblies are mscorlib (1,5mb), Xamarin.Android.Support.v4 (1,4mb), Mono.CSharp (1,2mb) and GooglePlayServicesLib (1mb).

Also the generated APK is not compressed, is this normal? APKs generated with ADT are compressed.

Any hints to reduce apk size?