I've recently discovered this approach, and I really like it.

I've looked at ways to make it more interactive / gamified, and I've made a prototype with with simple interactive stories (text adventures), designed for language learners (https://lingostories.org - 100% free).

I'm still trying to figure out what the next steps should be to make it more useful, but some people already enjoy it.

The main thing learners utilizing comprehensible input need is volume, so if you actually want to make it useful as more than a one-off novelty, your priority kind of needs to be in pumping out the content (while keeping it relatively interesting since that's also important). That's really the hard part. I will also say that I'm not personally convinced that "here's the words you heard, now tap them in order" minigames are very helpful. Other than that, the features and functionality are nice. Reminds me of Duolingo stories, which is their best content IMO.

Thanks a lot, I appreciate the feedback! Indeed, Duolingo Stories are the part of Duolingo I enjoyed the most too.

Taping words: I sometimes find it useful to focus my listening and try to recognize the words. But I'm not sure about the design here and maybe I should disable it by default. Thanks again!

With old-school graded readers. Turns out that the people in past centuries who we ridiculed for their antiquated approaches for learning languages all spoke multiple languages.

They didn't have comic books, though, which are another good source of interesting reading material that also comes with elaborate visual hints to what is being said. If I were trying to learn Mandarin, I'd scour the internet for bootleg scans of Jademan comics from the 80s.

Yes. That's how I learned my native language and that's how I learned other languages. Super effective, and super fun. No rote memory whatsoever. BTW, Chinese didn't have a tradition of producing comic books, but they were big on turning classics into so-called 小人书，a perfect source for learning authentic, highly contextual, yet simple Chinese. Here is an example: http://www.laohuabao.com/xiaorenshu/gudian/9/113957717.html

Slight aside, but I learned to read with Asterix & Obelix & Tintin. The Asterix series in particular was fantastic for reading the same story in difficulty languages, and savoring the wordplay in each, and how the translators played with things. Having visual context to go with the words themselves was such a boon, I really am surprised the approach isn't given more legitimate respect.

Comic books are especially helpful for conversation because they are often written in that sort of "what one would really say" style, which is extrememy helpful for speaking more native. When I was learning Finnish I found a set of translated Garfield books that were really helpful.