Have you considered adapting your app for deaf people?
A friend of mine developed a pronunciation practice app for deaf speakers of Korean as a student, which won them an innovation award. But according to my friend, the pronunciation score (which was based on comparing spectrograms or something) didn't work all that well, and the award was mostly due to the non-technical team members making up a heart-warming story to promote their project.
I assume your feedback system is more advanced (can you share some details on how you determine what recommendations to make?) and would also work for deaf speakers. But you can't really assume familiarity with another spoken language, so you'd probably need explanations specifically tailored to deaf people.
A friend of mine developed a pronunciation practice app for deaf speakers of Korean as a student, which won them an innovation award. But according to my friend, the pronunciation score (which was based on comparing spectrograms or something) didn't work all that well, and the award was mostly due to the non-technical team members making up a heart-warming story to promote their project.
I assume your feedback system is more advanced (can you share some details on how you determine what recommendations to make?) and would also work for deaf speakers. But you can't really assume familiarity with another spoken language, so you'd probably need explanations specifically tailored to deaf people.