Just a quick note – the "Configure Your Exercise" step was a bit confusing. It took me a while to figure out what “Number of Gaps” even meant, since that’s not something I’d usually think about configuring.

Also, choosing an input method felt tricky. I hadn’t used the product yet, so I didn’t really know what to pick or what would work best for me.

Once I got into the app, everything made sense, but it wasn’t clear upfront.

Maybe you could let people start with a default setup and explore the options while using it. That way, the learning happens more naturally and the config step doesn’t feel like a blocker.

Just a friendly heads up, for the Japanese exercises the video starts just a bit too late and the word you're listening for is cut off. This might only be pertinent for languages where vocab words are appearing at the beginning of sentences, French and Spanish didn't have "gap words" at their sentence start for the few exercises I tried.

This is a cool app, I would have enjoyed this when I was grinding on Japanese back in the day.

My biggest complaint about Duolingo is the lack of feedback about how to improve. There are several words whose pronunciations I think I correctly have but the app doesn't understand my pronunciations ever. There are also some words whose dictionary translations aren't provided or are used differently than the translation help offers. Without feedback to ask questions and get answers it's very frustrating.

Great idea, nice proof of concept. It'd be nice to see a translation into English after we finish the sentence, as it'll inevitably introduce words I don't known yet, and there's a learning opportunity.

This looks great! A humble request: a more button that I can press to sign up for an email when a language I seek gets added.

Nice, tried it. Looks cool. On the phone the drag and drop is a bit tricky. Dropped a wrong word and it got score emediatly as wrong, even though I was going to fix it. I expected scoring to happen after I click "submit". But maybe that's the same in Duolingo, no idea.

Super cool that you've got Dutch as well! I make https://hetnederlands.com, would be happy to do a link exchange or something like that. Feel free to get in touch lars@hetnederlands.com

first screen is 'Select a language' - maybe good to make clear if that's your own language, or your target learning language

Would love to see a way to understand the english equivalent of each word. As it stands now you aren't really expanding your vocab if you are just listening and copying what they say without knowing the word's meaning.

I think one other point to consider in the content filtering: One of the first examples that was shown to me had in-video subtitles, which made the exercise too trivial, as the answers were essentially given away.