It is so expensive to buy premium and very very irritating when you are out of gems and it's such a long wait to get new hearts. I really hate it when you are near the end of your lesson and get it wrong so have to wait 15!!!! Hours for 5 hearts. It is good to learn but personally I think it is very hard to understand a language with only 5 hearts and such a long wait, yes premium is a think but it is very pricey