Hey guys! - I am wondering if you guys have ever dabbled in reverse engineering and I want to know how to

1.How to reverse engineer classes
2.Deobfuscate different apk protectors like ProGuard or DexGuard


If anyone can share with me some recourses so I can help give back to the community that would be awesome - Because I already know some programming languages and I would love to reverse engineer protected APK's to make some pretty cool stuff, Thank you! <3