Split apk into smaller pieces for Google Play,APK expansion files

How can I break up my APK file into smaller pieces for the 50 meg limit for Google Play Store.

My game is over 50 megs in size, I have stripped out and compressed everything.

Thanks

I wrote a small tutorial for this. Hope this helps.

here is the 1

user assest bundles.

and i think this link is much useful for you
[Click Here][1]

[1]: http://forum.unity3d.com/threads/111220-How-did-Shadowgun-reduced-APK-to-6-MB,what about assest bundling

doesent matter the platform i think.that solution is universal.