Pros:

1. It is an open source app which makes improving it easier
2. It has courses that are available in different languages
3. It doesn't require internet connection which makes it accessible anytime
4. There are a lot of courses on the platform
5. It is a free app
6. It works on different kind of operating system including windows, Linux and Mac OS
7. It offers self-paced learning
8. It has a data synchronization feature allowing administrator to view offline usage information
9. There is an individual feedback feature giving each person to see his.her progress

Cons:
None I could see as it is just wonderful and a great help for students to learn