Parts of the binary on the App Store are encrypted so we can only get limited information from it, but the whole app bundle is available and the rest of the files are not encrypted. We’re building a startup to help monitor, analyze and reduce app size and I was able to quickly grab these statistics from the tool we’re working on, here’s a link to a quick demo: https://www.youtube.com/watch?v=3x-hLxxUNm8

It is also quite easy to decrypt iOS applications using jailbroken devices.