Launch HN: Issen (YC F24) – Personal AI language tutor
94 comments
·June 26, 2025anavat
Thanks for working on this! Language learning really needs a breakthrough.
Now, I tried the web app and chose to learn Greek as a beginner. And while I had better experience with your app than with ChatGPT or Gemini voice modes, I still got lost 5 minutes in because the AI tutor doesn't seem to have a plan for me, nor does it "see" my struggles. For example, after asking me about a hobby, it gives me a long sentence in Greek about how how it is nice to hike in mountains. Being absolute noob I cannot reply to it, nor even repeat it. And I don't even know what it is expected from me at the moment. A human tutor here would probably repeat a part of the sentence with a translation and ask me to repeat, or would explain something. The AI just sits there waiting for me to make a sound, and when I make it, it goes on on a tangental subject of beach vacations. :)
Again, this is still relatively not bad, and I'm going to give it another try.
drakonka
I had a similar feeling with Swedish just now. It isn't really much different than conversing with ChatGPT in advanced voice mode - it's up to me to drive the conversation and it all feels quite arbitrary (and I find myself instinctively falling back on topics I know how to talk about, which quite defeats the purpose). I was hoping for a more structured learning plan that strategically expands my comfort zone and skills in a guided way.
mariano54
Thanks for the feedback. Yeah we need to improve the beginner experience, it's more tailored towards intermediate/advanced students at the moment.
55555
I'm an advanced learner but I stopped after a few moments because it's boring. It's asking me questions that you'd ask a beginner (although a beginner wouldn't understand the questions). It just asked what food I like to eat, where I like to travel, whether I like the weather, etc. I have a language tutor IRL and I have found that we run out of things to talk about too. So we often find ourselves just discussing the latest events from the news. I think you should feed fresh conversation topics daily from a data source like the news, localized to the user. There are global news APIs you can subscribe to.
drakonka
Do you mean that the experience is meant to have more structure if you pick the intermediate or advanced level? (fwiw I did pick intermediate for my Swedish level in the app).
My thinking is - I can have unstructured conversations with Advanced Voice Mode or in real life here in Sweden. What I'd really appreciate is a guided learning experience taking me up from intermediate/slightly above intermediate to fluent in the most efficient possible way (as opposed to just having us 'ramble' about random topics of my own choosing).
Ocha
So basically if you are starting a new language from zero, then this is not for you?
candiddevmike
Why wouldn't intermediate/advanced students just talk directly to ChatGPT? From what I see, I thought your value prop was for the beginners.
mattbee
I paid for Memrise to polish up French. The scripted lessons alwere great but it dropped me into an AI conversation assistant that did exactly the same. It forgot the vocab and grammar level that the scripted lessons has taught, and often broke into idiom. I haven't picked it up since.
Nadya
I'm a Memrise beta member w/ lifetime premium access for my contributions to the site in its early days. I cannot recommend anyone use Memrise for anything nowadays it has been so heavily enshittified. In fact, I recommend against using it in favor of Anki (Memrise's biggest strength over Anki in the early days was the community mnemonics and courses (Anki equivalent "community decks") - none of which really exist in any way today).
I tried following the modern Japanese track on Memrise and was appalled at how bad it is nowadays.
kevmo314
I think this is a pretty big limitation of the architecture (STT->LLM->TTS) they've chosen. The intonation around struggling to speak or difficulty with certain phrases is totally lost when the text is transcribed.
koakuma-chan
I think the point here is for you to practice (i.e. develop "muscle memory" for speaking), not to learn.
deanc
I built a basic version of this for myself with a prompt in chat gpt in an afternoon. It's great that you've built this yourself, but where's the magic? If it's your prompt it can probably be extracted in a few minutes by those who know how to do so.
M4R5H4LL
Why not finish, publish it to the store and get income if it was that straightforward? There's a long way to go between a toy application to demonstrate a product, and something on shelves actually selling. In other words, you can most often quickly tackle the concept or trivial parts of an app, but it's much harder to get a real product out, even if the implementation looks straightforward on surface.
deanc
That's exactly my point. This is at best a toy application driven by a prompt that many people will be able to extract and recreate. Putting the pieces together is easy and letting someone talk to an AI is not a particularly difficult problem. Creating magic and making people come back to learn the language is entirely different and I don't see anything magical here.
iNic
Very impressive, but still has the same problem that seemingly all voice modes that I have tried have which is that the Cantonese voice has a Mandarin accent, and sometimes just straight up uses Mandarin pronunciations.
dataviz1000
Luis von Ahn spoke in the early 2010s—probably around 2014—at The LAB in Wynwood, Miami. He recounted how his fascination with crowd-sourcing led first to reCAPTCHA and then to his latest venture, Duolingo. He made it clear that his real passion wasn’t language per se, but building a crowd-sourced human translation service as a business model. At that point, Duolingo had roughly 24 employees—and, much to his surprise, only two were focused on the crowd-sourcing engine. He explained how they’d enlisted some of the world’s leading language-education researchers as consultants. Their very first question: “Which part of speech should learners tackle first?” The experts confessed they didn’t know, so the team gathered the data and used A/B testing coupled with statistical analysis to pinpoint the answer.
Today, it’s not only easier than ever to launch a platform to challenge Duolingo, but its core product—its crowd-sourced human translation service—has been distrupted.
This morning, I found myself thinking about how all those decade-old learning platforms—like Coursera, as reflected in its ever-falling stock price—are being distrupted.
Your product looks awesome and I hope you distrupt all the language learning platforms. Thank you for sharing.
(I had ChatGPT fix my grammatical errors and now this comment doesn't sound like me, sorry.)
thinkingtoilet
>We didn’t want to focus too much on gamification.
Thank you so much for this. Duolingo is literally unbearable because it's so gamified. I'll try it out later. I've seen a few of these apps, can I seamlessly go between my native language and the language I'm trying to learn? If I am trying to learn Hindi, can I ask a question in English in the middle of a conversation?
vjerancrnjak
The app is optimized on the whole population, not on individual level. They even publish papers on global optimization.
These kinds of learning apps are destined to become mediocre over time.
The learning metric is so easy to capture, the learning content so easy to produce, yet no one has an individualized loop to make learning work well.
For example, I'd press "Training" on Duolingo, and would get nowhere. Same lessons all of the time. Bread and water.
mariano54
Yes, we've spent a lot of time getting the STT and TTS to work seamlessly in multilingual, it works pretty well!
vunderba
The ChatGPT mobile app in hands-free voice conversation mode works quite well for language practice with one important call-out: you have to give it a topic at the beginning otherwise it won't be able to drive the conversation forward and will stick to banal pleasantries.
What I usually do is pick a random blurb in the news and paste the entire thing along with the Reuters link at the beginning and inform ChatGPT that we'll be carrying on language practice specifically over that topic of discussion.
I've used this to carry an hour long foreign language practice in Spanish while walking my husky. Just put the phone in my pocket and go. If you're an intermediate/advanced learner, it's a pretty decent solution.
In fact, you can actually instruct ChatGPT that you are going to speak in your native language, but ChatGPT is only allowed to respond in the target language if you just want to focus on practicing listening comprehension.
I'd be interested in hearing how significantly improved Issen is over this.
mariano54
Yeah, agreed, we started with a similar observation. These voice models are getting better quickly.
You do need an app to create a holistic learning experience just for language learning. Customized curriculum, tons of prompting, AI models chosen for transcription accuracy, flashcards/dictionary, etc.
We also support hands free mode, and many other things are customizable like slang, speaking speed, target language usage, etc.
mtalantikite
This looks great, congrats! As someone that has gone through Assimil courses and done lots of comprehensible input for various languages, language production is typically the weak point that isn't covered well. I've done plenty of lessons on iTalki, but I've been wanting something more structured and this seems like it could cover it. Definitely going to give it a shot!
The feature request I make for all language course makers: please consider Bengali support in the future! It's wild to me that the 7th most spoken language in the world, with a deep culture around literature and poetry [1], gets zero attention from language course makers. I can buy an Assimil course on Breton, spoken by 200k people, and not Bangla, spoken by 284 million.
clbrmbr
Nice! I’ve wanted this for years.
Suggestion: you may be able to integrate SRS into the conversation. —- you could encourage the model to use certain words, and more importantly you can track the student’s active use of words that are on the review list, basically acting as if it were an SRS step. — this could totally eliminate the need for flashcards.
mariano54
Yeah this is a really great idea, perhaps you can sample tokens based on some kind of SRS and I+1 sentence system. Kind of like a graded reader but for speaking. Will definitely look into this in the future
tmaly
I want to build some AI tutors at home to help my kids with some of their school subjects and interests. I help them with subjects I know, but for other subjects I often do not have enough background. What are you best tips/ideas/design patterns you learned when making this app?
mariano54
Some random tips which could help you
- Don't go over 10k tokens in the prompts as the intelligence and memory degrades
- Summarize sessions and save the summaries, potentially summarize the summaries as well
- use VAPI or realtime api if you want to build fast. Building the full pipeline takes a while
- try out different models and see how personality varies. Our favorite is gpt4.1 with temperature 1.
- goal system. The promot should always contain the current goal, and the next goal. Evaluate goals with another LLM, and dynamically change the prompt
accidentalrebel
Thank you for sharing this.
I've been learning Arabic, and I noticed that the app uses Arabic script right from the start. This can be quite challenging for beginners who haven't learned how to read it yet. May I suggest adding an Englishized (romanized) version of the Arabic text to help ease the learning curve?
It also seems to not listen to me when I asked to give me shorter sentences. It seems to not care that I'm struggling despite my pleading.
I later switched to Spanish, which was a better experience. This one seems to listen to me better. I can ask the tutor to repeat what they said in English and give me shorter sentences, and thankfully, it does.
Interacting with the tutors does feel I have to drive the conversation which is taxing. Compared to a human tutor, where I feel assured that I can be guided properly.
Still an interesting app. Would love to try Spanish some more, in the future.
itake
I'm trying to learn vietnamese, but the lessons are really really rough and borderline bad advice.
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AI: Anh mệt is good if bạn are a man speaking about yourself. You can also say, “Em mệt” if you’re a woman.
this isn't correct. If you are of "older brother" age and are male, you say Anh. Em is for if you are "younger person" (does not matter the gender). Women tend to prefer being called "em" (even if they are older), because women prefer to be identified as younger than their true age... But that doesn't mean you can't call younger men em.
A good tutor would know your age relative to theirs and explain this context.
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It would say english phrases with a vietnamese accent.
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It also would give me really complex vietnamese phrases that I am not ready for. when I prompt for an explaination or translation, it would get off track from the original thing we were learning.
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Way more people in Vietnam (and the globe) speak southern Vietnamese, but the tutors seem to be from north Vietnam.
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The STT also was very forgiving if I pronounced things incorrectly. Or it would confuse english and vietnamese. I would say, "Phai", but it heard "bye"
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I was ready to pull out my credit card, but I can't trust it to teach me the right information. I pay $160/mo for Vietnamese tutoring ($20 per class). This would be way cheaper and I don't have to schedule my classes.
tempodox
This sounds very much like the kinds of mistakes that LLMs typically make. It's a pity, I would love a good language learning platform.
iandanforth
Alright, having tried this with Japanese I can say it's frustrating. As a near complete beginner the tutor kept speaking in Japanese even when I said "sorry I don't understand" repeatedly and then when I asked it to start in English and then gradually transition to Japanese it lasted all of one sentence in English before switching back. I can totally see how this would be useful conversation practice if you've progressed that far, but I'd love to have something for even earlier beginners. Also since many of the models you use are natively multi modal this could readily integrate visual media for discussion and grounding.
Also, for the transcription it would be great to get pure romanji to start with!
antonaf
Yes, I can understand and empathize with your experience. Quite honestly our current focus is more for B1+ students. That 0 -> 1 / bootstrapping of the language is much better served by traditional material that is less talking / listening-heavy.
55555
Unfortunately, I think you will soon learn that the market for advanced language learners is 1/500th the size of the market for beginner learners. But thank you very much and please keep focusing on us.
null
Hey HN, we're Mariano and Anton from ISSEN (https://issen.com), a foreign language voice tutor app that adapts to your interests, goals, and needs.
Demo: https://www.loom.com/share/a78e713d46934857a2dc88aed1bb100d?...
We started this company after struggling to find great tools to practice speaking Japanese and French. Having a tutor can be awesome, but there are downsides: they can be expensive (since you pay by the hour), difficult to schedule, and have a high upfront cost (finding a tutor you like often forces you to cycle through a few that you don’t).
We wanted something that would talk with us — realistically, in full conversations — and actually help us improve. So we built it ourselves. The app relies on a custom voice AI pipeline combining STT (speech-to-text), TTS (text-to-speech), LLMs, long term memory, interruptions, turn-taking, etc. Getting speech-to-text to work well for learners was one of the hardest parts — especially with accents, multi-lingual sentences, and noisy environments. We now combine Gemini Flash, Whisper, Scribe, and GPT-4o-transcribe to minimize errors and keep the conversation flowing.
We didn’t want to focus too much on gamification. In our experience, that leads to users performing well in the app, achieving long streaks and so on, without actually getting fluent in the language you're wanting to learn.
With ISSEN you instantly speak and immerse yourself in the language, which, while not easy, is a much more efficient way to learn.
We combine this with a word bank and SRS flashcards for new words learned in the AI voice chats, which allows very rapid improvement in both vocabulary and speaking skills. We also create custom curriculums for each student based on goals, interests, and preferences, and fully customizable settings like speed, turn taking, formality, etc.
App: https://issen.com (works on web, iOS, Android) Pricing: 20 min free trial, $20–29/month (depending on duration and specific geography)
We’d love your feedback — on the tech, the UX, or what you’d wish from a tool like this. Thanks!