The app can teach everyone has no age, letters and numbers auditory and visual.With personal thinking, I recommend you download the application if you really do not know how to hear letters or numbers in English, because you click on a number or signal we will hear a voice that speaks in English.It really helps everyone, thanks for choosing to download the app and understand a little more English and listen.Hope I helped you learn something more interesting and Id love to share with friends and family. Thank you and good day. From me Sabrina