A “Listening Placement Test!” That does sound like a great feature. It sounds like somebody at that time understood learners needs, especially auditory learners! I like the ability on both the website and app to slow down or speed up the dialogue, loop it endlessly, etc. I mainly use a Chromebox desk setup to study and have and use a large cell phone flashcard deck (with the “forgot, not quite, and got it” options).
Are most Chinese polyglots? Were the foreigners you taught from a bunch of countries or just a couple? I get a kick out of CGTN broadcasting in 5 different languages: It at least shows an awareness and appreciation of all those languages, cultures, etc. Studying Mandarin makes studying French, Italian, etc way, way, way easier for me. I miss when CPOD was SpanishPod, ItalianPod, etc. It was easy one stop shopping for many languages! The WayBack Machine gives a link to SpanishPod.
I enjoy your posts: Thanks for sharing all your strategies, techniques, etc. It is very interesting to read about!