Mashups Learning from basic

[#1]

Hi all,

I am new to Qliksense and i want to learn everything about Mashups and Extension objects.

I watch a  few videos from you tube Mash-Up APIs part 1 to 4 but somehow could not relate to content https://help.qlik.com/sense/2.1/en-us/developer/#../Subsystems/Mashups/Content/mashups-introduction....

Later i realized this videos were as per Qliksense 1.1 version.

Do we have some other videos for mashups.

Can anyone tell me how to learn everything from basics in Mashups.?

Thanks

Khushboo