You will not need to because the new app includes access to the available pronunciation trainers in whatever language(s) you want to study. That said, if you’ve already used your trainer then you’re not going to want to look at those flashcards all over again. If your language is not yet out in beta (because if it is, it also has the pronunciation training in full), it’s best to use your trainer in Anki before the app comes out, get the value out of it, and then move to grammar/vocab in the new app.