Feedback Eliminator suggested improvement:
I feel like Feedback Eliminator has amazing potential, but the way that the lessons are set up now are kind of a crapshoot. I’m having difficulty gaining an intuitive sense about exactly which frequencies I’m hearing.

My suggestion is to stay consistent: e.g. start with ONLY 3 bands (e.g. 100Hz, 1000Hz, 10kHz), and quiz you on ONLY these 3 bands. Yes, ridiculously simple, but your ears are getting accustomed to these 3 bands AND ONLY THESE 3 BANDS. Level 2 would be to add a band (e.g. 315Hz) but ONLY quiz you on these 4 bands. Level 3 add another (e.g 3.15kHz), etc. progressively adding intermediary (or upper/lower) frequencies. After, say, every 3 newly added bands, the next level or two will quiz you on ONLY the newest/added frequencies, but give you the option to choose any of the learned frequencies. For each level after maybe 6 added bands then limit the choices to a subset of the learned bands (kind of like now), then slowly add more choices within the “learned” bands (again, similar to how it is) before adding another band. Continue this process through all 31 bands (and/or allow the user to limit the extremes based on playback equipment limitations - i.e. headphones that can’t produce frequencies below 40Hz or above 16kHz). I strongly believe this will tune your ear faster than randomly selecting ANY of the 31 bands as it’s set up now. Thoughts?