Hi @aarushi_tewari, this will depend on where you are planning on adding the link to the app. Since the app is not only free and educational, it would be ideal to place it in the Bonus Lecture, which is the last lecture of the course. You can learn about the guidelines here.
If you have any further questions or concerns, I highly recommend writing to our team at email@example.com - they'll be happy to help! 🙂