what is tiny cards? Do you have to pay lingots for it?
Nope. It's a website completely separate from duolingo, though it's made by the people who made duolingo. You can use your duolingo account to log in, and set things up and ... you can learn things other than duolingo has ... brail, sign language, Icelandic, Japanese, Latin, etc.
You can also learn non-language-related stuff, like science and history. It's pretty cool. And free.