The app is a nice game that teaches you 46 words. What remains a mystery is why the programmers after having made the effort to program it did not add a longer list of words. Maybe subsequent lessons once you were able to complete the first 46 words easily. What could have been a learning tool is instead just a tiny game. They should add the radicals. Then all the words in hsk 1. And then the rest. The ads are not intrusive at all.