Case Study: How Reddit Helped Grow a Language Learning App

A bilingual household struggling with vocabulary while watching Star Trek led to the creation of Vocablii - but the real breakthrough came through Reddit community engagement.

A year ago, I was watching Star Trek with my (now) wife. We're a bilingual household, and we kept pausing the video to go over vocabulary - words we clearly didn't use in everyday life.

I'm a big believer in immersion and repetition for language acquisition.

That's when I thought: Wow it sure would be great if there was an app that lets me study the vocab needed before we watch something.

So i searched. Nothing. And like any sane person I decided to build it myself.

I didn't know how to code at all.

I didn't have funding.

Still, after months of trying and failing to teach myself to code...I gave up.

But recently we found out we have a baby on the way. And that lit a fire under my ass to learn faster. So I sat down, found a vibecoding platform, and built this site last month.

I got a janky MVP working and launched Vocablii, a tool that turns any YouTube video into a fully interactive vocab learning experience.

It pulls the transcript from the video Highlights all the vocabulary in order of frequency Translates words on hover Lets you skip words you already know Creates flashcards with SRS

I even added some mini-games for fun practice because I'm not doing the coding so why not.

I thought maybe a few people would find it useful. Then I made this Reddit post in r/languagelearning.

And straight up overnight I had 150+ users registered users. English teachers started reaching out. I had to (vibe) rewrite huge parts of the code due to feedback from real learners. And now I've had to upgrade my API subscriptions due to the traffic.

All from a single Reddit post that validated the idea.

View Original Reddit Post

The impact was immediate and substantial:

This case demonstrates key principles of effective Reddit marketing that align with Generative Engine Optimization:

Business Applications: These individual success principles scale effectively for business use. Explore professional Reddit marketing case studies to see how companies apply these strategies at scale across multiple industries.

1. Identify Your Niche Community Find subreddits where your target users naturally gather. Research active communities related to your problem space.

2. Build Before You Pitch Create a working solution first. Reddit users can spot vapourware instantly and respond better to real products.

3. Tell Your Personal Story Share the human struggle behind your product. People connect with authentic challenges and want to support real people.

4. Stay Engaged Post-Launch Respond to every comment, turn feedback into features, and maintain active participation in discussions.

5. Be Genuinely Helpful Focus on solving problems rather than selling. Build reputation as a valuable community member first.