Google has doubled the limit it places on Android Package (APK) files for apps in Google Play to better support richer apps and games .
Read moreWhy are my apps getting bigger?
Also, installed app size has greatly increased due to android shifting from delvik to ART model . But that said, ART enables android devices to run apps faster. The competition in the android market has left developers with no choice but to use libraries that give really cool effects and make the UI look a lot better.
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