I opted for the paid version for exactly the same reason, but I was sorely disappointed to learn that they don't allow the app to be installed in my home country when I went there for a visit and was hoping to introduce my young nephews to the joys of learning a foreign language. It happens that third world countries don't generate enough ad money to be part of the free language learning for all mantra. Needless to say, I didn't renew my subscription. I must admit though that the app contributed toward my goal of attaining reasonable proficiency in Portuguese in one year, though I got much more out of obstinately listening to podcasts and regular radio even though I understood little at the beginning, and also making native speaker friends online. I used https://www.hellotalk.com/, an app to meet language learning partners to chat with, and where Brazilians happen to be extremely active and eager to exchange with people willing to help them with their English or French.