How To Modify .APK Files

Have you ever wondered what makes up the contents of an Android application package ("apk") file? Well, the folks over at Android Guys have some details -

The extension Google uses for Android applications (APK) may seem a bit complicated at first, but it really isn't. In fact, an .apk is nothing else than a .zip file disguised as an .apk. That's dumbing it down, but you get it. Essentially, if one wanted to see what's inside an app, they would just change the extension of applicationname.apk to applicationname.zip, unzip it. And there you have it: The contents of the .apk!

The article doesn't stop there, though, as it gives information on tools to reverse engineer the contents of extracted files. As a developer, I'm seriously torn by processes like this, mind you, as I believe in intellectual property rights and protections. Any application I have ever intended for developer community to extend and enhance has always been made completely available (source code and all). So if you decide to try this out - please do so with the proper respect to the developers out there.