So much of our Android experience is dependent on modifying various APKs. Modding, theming, ROM and app developing in one way or another often require some sort of tweaking, modifying, or refashioning of an APK. So XDA Senior Member XperienceD has decided to create a 'Definite APK Modding and Theming' thread intended for everything to do with modding and theming.

XperienceD starts this thread off with a thorough, 'all-in-one' guide on APK decompiling and recompiling, signing and zipaligning, .9PNGs, and flashable CWM zip files. Categorized into these respective sections, the guide comprehensively covers every tool, step, and code with sufficient detail and covered minutiae needed. He does so in such a way that any novice or aspiring developer without an engineering or computer science degree can follow. XperienceD eases the process with asides of advice, links to other guides, external resources and sites, and the inclusion of numerous helpful visuals and videos.

XperienceD's guide is most definitely one of the more thorough and comprehensive guides that I've come across. Not only is it a great starting point for the beginner, but even the experienced folks may find the guide worth a read and a bookmark. So if this has gotten you curious, make sure to check out the original thread for more information.