Can obfuscation be applied on certain parts?

Question

I am newbie to this field. I am still learning from your wonderful contributions, help and guidance.

I have had an app that i want to study in-depth. How the the it is constructed? What components that are used? And the like.

I did some decompiling operations with different tools and I get different results. What confuses me is that when I decompile with jadx (online one) I get java extension files, resource and so on but i do also see .dex file 1&2. I don't know if the obfsucation was done on particular parts (3rd party) or what?

What do you think guys? Does the proguard can be applied on certain parts in the app or as a whole.

I can share with you the apk file and the results too.

Thanks in advance and have a good day.

Answer 1

Multiple .dex files are created mostly in cases when the number of methods exceed the maximum one for .dex files, which is 65536 functions per file.

Yes, ProGuard can be used to obfuscate only specific classes/function/methods, take a look here, especially to the options starting with -keep