This application has free version too but with the less topics.

Features of Github tutorial pro:

1.Basic section where all the basics of github is presented.
2.Intermediate section.
3.Advance section.
4.You can take test in the "Random test"
5.Fully materialized.
6.Eight new topics.

If you have any suggestions/queries then you can send me a mail ( vivek2neel@gmail.com )