Even with the constant barrage of ads, for the first 30 days this was a useful app and I had high hopes for learning a new language. Now 55 days in, and I'm completely turned off. It is one thing to pay for the monthly subscription (for hearts). But you also have to pay for gems if you want to complete the tests in a reasonable amount of time at the end of each lesson (it's frustratingly slow to acquire gems otherwise.) I'm fed up with this app and removing it from my phone.