What I learned building an AI language learning app

Part 1/4: Intro

In the first half of 2023, I, Patrick Coleman (a longtime startup business guy), and my friend, David Gaynor (an experienced engineer/founder), built the first version of Yaya. During this time David also taught me to code.

Screenshot of the Yaya web app, showing a story in Spanish
Yaya v1.0 circa summer 2023

Reader: Wait wait, what is Yaya"

"Author: Yaya is a foreign language learning app that uses AI to generate dialogs, stories, and more."

"Reader: Oh cool, so is it really popular?"

"Author: Well...

The truth is the first version of Yaya never saw the growth we wanted. We learned a ton, but in the end, we moved on from Yaya v1.0. I ended up moving on from the project too. David kept going at a more relaxed pace, and on March 15th, 2024, he released a massive update (more below).

You hear a lot about the big startup successes. This won't be one of those stories. In this blogpost series, I'll share an inside look at when things don't quite work out. If you're interested in AI, software startups, language learning, learning to code, or maybe just if you know me, I think you'll find this series interesting.

Yaya v1.0

The first version of Yaya used AI to generate reading content at an appropriate learning level in (almost) any language. It follows the language learning principles of comprehensible input and spaced repetition. We built it using ChatGPT, Next.js, Firebase, and a handful of other tools. And we bootsrapped the business, not taking any outside money.

To get a better idea of how Yaya worked, watch this short video overview:

Yaya v1.0 in 2-minutes

The core user journey:

  1. Generate content in your target language
  2. Read and listen
  3. Study words and phrases you don't know
Screenshot of the Yaya web app, choosing a language and level
Choose your language and level
Screenshot of the Yaya web app, customizing reading content
Customize your reading content

With tons of prompts in different genres to seed your ideas

Screenshot of the Yaya web app, showing a story in Japanese
Read and listen in your target language
Screenshot of the Yaya web app, looking up a word in Japanese
Look up words and phrases you don't know

Includes pronunciation, audio, grammar explanations, and example sentences

Screenshot of the Yaya web app, vocab review page
Review with flashcards

Built in spaced-repetition (SRS) and Anki export

Screenshot of the Yaya web app, add vocab to a generated story
Or include your due vocabulary in a story

Want to go even deeper? Try Yaya v1.0 for yourself. Or if you prefer video, watch this 11-minute deep dive.

Yaya v2.0

The new version of Yaya focuses on students working with language tutors. It's got a ton of features for language learners and tutors to use together during sessions and individually to study or prep.

Screenshot of the new Yaya web app, showing content in Spanish

Now featuring additional AI prompts, new content types, writing practice, editable text, chat, error correction, and more

Screenshot of the new Yaya web app, showing content in Japanese

Support for native and romanized pronunciation in logographic languages (like Japanese)

Needless to say, we're very optimistic. Give it a go!

So what's next?

As for Yaya, David will keep working on it, using the features we built for v1.0 as a foundation. I'm excited to see it grow and evolve. I'll be using it to study Korean.

As for me, I'm looking for work again. I'm especially intested in AI, edtech, or dev tools startups. If you need a smart, hard-working business generalist with a technical background, consider hiring me.

A small man standing on a book and looking out a window with two landscapes

Looking ahead (image credit: DALL-E)

I stepped away from Yaya last summer for two major reasons.

First, I realized that I enjoy working on the business side of startups more than I enjoy spending my days coding. David wants to keep Yaya small, so there's no need for a full-time business person.

And second, I wanted to travel the world with my wife. This meant pausing professional work and drawing down savings. David wants to keep bootstraping Yaya. I need a steady salary right now. Life in San Francisco is expensive. But I love it here, it's close to family, and I can't imagine living anywhere else.

In the beginning, I was fantasizing about Yaya becoming massively financially successful overnight, while also telling myself it'd be fine if this was just a good opportunity to learn to build software. In the end, it was the latter. And I'm pretty happy with that. I think it'll make me a lot better at whatever comes next.

I also want to say a huge thank you to David! He's been a true friend and mentor throughout this journey. I learned a ton hacking on Yaya and had a great time doing it. I'm sure I'll be buiding something from scratch again someday.

Thank you too for reading this first post in the series! Like Netflix, I'm releasing everything all at once. If you like to binge, have at it. Or check back weekly on social media if you prefer to have it coursed out.

  • Part 1 (this post): An introduction to Yaya v1.0
  • Part 2: A deeper dive on the lessons learned while building Yaya
  • Part 3: The backstory: how I got to Yaya, what I did, and our early iterations
  • Part 4: The tools we used to build Yaya and some final thoughts