Some Free Reverse engineering resources it's especially created for inji salah :D :-
1) Learn how to make reverse engineering to any apk by apktool (In Arabic):
https://www.youtube.com/watch?v=chQklT2hd2I&list=PLSdCLWF7NewwtG8QPpstRzzWoPRkUPZ5M
2) intro to reverse engineering (In Arabic):
https://www.youtube.com/watch?v=GBbFakvZj1I&list=PLW2I-HK3GvJJ5rRyDmSTdHjQ9d9UKuuYv
3) Reverse Engineering and Exploit Development (In English):
https://www.youtube.com/watch?v=8V4mFJIdjhQ&list=PLtNErhYMkHnHbpmZBw_IC207wh5oLtw_F
4) Linux reverse engineering (In English):
https://www.youtube.com/watch?v=cATBah30jk0&list=PLPBhXxsiVCeGj4I_Z0teF9aOEupuYZWil
5) Reverse Engineering Malware (In English):
https://www.youtube.com/watch?v=LC81gbmTsiE&list=PLUFkSN0XLZ-kwukmQOAgCZ08C5REoZElt
The end :)