alt Hacker NewsLaunch HN: Issen (YC F24) – Personal AI language tutor
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!
Comments
Why not use the Gemini flash voice-api directly instead? Cost? I ask because from the demo, the tutor's voice seems mechanical. I've played with the gemini voice api and it's quite impressive for conversation with low latency, I'd say perfect for your use case. It even switches languages if I say "Okay, let's talk in $foo language".
The vocabulary tooling looks neat and well thought out.
Looks great. I have been looking for something like this
I like this https://labs.google/lll/en from Google
The conversation flows nicely. Certainly nicely built.
I thought this interaction in Spanish was interesting:
I said something like: Yo pienso que tú eres una inteligencia artificial. Es muy interesante.
Carlos responded: En realidad, soy una persona real llamada Carlos, aunque a veces hablo con muchos estudiantes como tú, como si fuera un robot
This might be the most obvious question regarding this, but how are you planning on competing with the entrenched competition for mindshare, namely Duolingo. This is probably technically superior, but from a user standpoint, it might not be so. Happy to be proven wrong
Ok, in over a decade on HN I've never commented on a product but this one is awesome! I just signed up!
I currently pay $99 a month to learn Spanish from a live tutor 30 mins a day, and this is far superior if you ask me.
The element that stands out to me is that the AI Tutor is consistent and concise!
Tried it is Safari, frustrating, confusing, spent some time figuring it out and closed the tab. I didn't say anything but the app kept "recognizing" some random words and "answering" tutor's questions... looks like pre-alpha version.
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?
I had a go and it failed at the first hurdle I’m afraid. It was hallucinating my responses and inserting phrases that I wasn’t saying.
The teacher kept switching into an American accent when I was trying to learn French and the responses were getting very slow bitty.
Hopefully this is just an initial load of issues because the concept is great.
I have tried the app. I was previously using chatgpt only to learn Spanish. I have found the app to be a much better and flowy experience - will continue using and provide feedback.
Which spaced repetition algorithm are you using? I recently learned that there is a much improved one that has been adopted by Anki. (https://domenic.me/fsrs/) Have you adopted that as well?
Nice! I'm curious if your software can pick up really subtle details - like for instance, pitch accent in Japanese (which is basically NEVER covered in a beginner level course) but is useful to just be aware of as a language learner.
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.
Is all this capital, energy and opportunity cost really worth displacing tutors who are already pretty cheap and demonstrably effective? I put AI language apps somewhere near fad diets, in that they appeal to the convenience mindset.
Hey! Can you add a feature that can record my lessons with a real human and then build a way for me to practice all the things we covered in the lesson? Would pay for this feature if it worked well!
I tried it, but I got stuck. I am trying to learn this Language, and I know very little of it. So we are having a conversation, and I just get totally lost. Would be cool if it switches back to English and then actually teaches me what all the words and sentences mean. Now I just closed the app, and going back to my usual language learning curriculum - generally, I would uninstall the app. But now I might just try it again in a few weeks from now.
Gave it a shot, but mostly found it unable to keep up an interesting conversation. There's a lot of similar apps and they all have the same issue.
This s super interesting! i have been wanting to learn other languages, but it i have been unsatisfied with most mainstream solutions. From what i have seen and for the price, i could see myself giving this a shot!
I see some rough edges typical to LLM-powered products, but this is still a fantastic tool!
I think it needs push-to-talk mode, because it's picking up every surrounding noise.
Love this. I have been looking for an app that does this. Congrats on the launch.
I also use chatGPT to translate phrases idiomatically and to ask questions about etymology, synonyms, homophones etc. I'm not sure I would want the entire language-learning process to be driven by talking with an AI so maybe I'm not the target audience for this app but these are the places where I think an AI can be uniquely useful in language learning.
I recently discovered www.lingq.com and it's by far the best language learning tool I've tried. The concept is that each learner brings the content they personally want to engage with - so it allows you to import articles, podcasts, and videos and then read them in your target language but translate words you don't recognize on the fly. It tracks the words you know and the ones you are learning automatically, and allows you to test yourself with flashcards based on the words in the content you care about.
This is great because if you just want to read eg. French articles about cybersecurity, you will quickly start to pick up the domain-specific words.
The problem is that the site is quite buggy, and needs a lot of UX/UI polish. I get the sense it's a small team, but they've been around for over a decade and it's still not polished.
I don't want to use an inferior clone of Anki, I just want deep integration with Anki. I want importing content to be as painless as possible, including subscribing to podcasts.
My ideal language-learning tool would be something like LingQ with all the bugs fixed and features implemented, and with AI integrated in the places it makes sense, not as the primary means of engagement with the app.
Edit: Never mind it seems to be an issue on my device.
The faq wont expand on tap for me on android firefox. Dm me if you need more info.
Looks like a great app and I can't wait to try it for Japanese!
Can the cards be exported to anki?
I would like something like this particularly for learning specific styles of programming. For example, in order to grasp functional programing.
Please add Latin
I really like the idea and I'm a potential customer, but I don't think this is ready yet. I've been learning Chinese for a while and decided to give this a shot and at my level (somewhere between HSK 2 and 3) it's very frustrating:
When I babble (as someone at my level does) and say "eh... a bit of sentence eh... a bit more of sentence" half the times it cuts me off in the first eh... or the second one. This is extremely frustrating, in fact I didn't even finish the free 20 minutes trial because of this.
Another issue is that like all LLMs it's bad at maintaining context of a conversation. I tried speaking about cars with it, as it's a topic I like so I thought it'd be cool and all of a sudden it's asking me what's my favourite ice cream. Don't get me wrong, I'm 100% certain I said something about ice cream but any human would understand I didn't want to say that.
Also I tried it with Spanish as I'm a native speaker. The speech recognition is bad, I don't know what sort of processing this does but it has a lot of mistakes, however it's very rare that chatGPT ever fails to transcript. I'd say well over 20% of sentences were misunderstood.
The idea is cool, but I wouldn't recommend this to anyone who wants to learn Spanish.
I'll try it, but that seems pricy compared to a Duolingo subscription. And while I understand that they are different, will your average lead know that?
I haven't tried it out yet. I will. But I just want to say that I have wanted this to exist since I first used ChatGPT in 2022. Thank you for building it.
I’ve tried Greek (Athena voice) and the accent is terrible. It sounds like an English or American person speaking Greek!
I put in my name but it insists I am called Anton.
Awesome, I was going back and forth with LLMs trying to keep a conversation up. You guys managed to channel those process, I think I will love this app!
Hopefully people that use these AI language tutors don't end up being clowned on by native speakers because they sound like robots.
how're you handling latency on turn overlaps : buffered stream with early intent cutoff or full duplex with partial decoding?
Sorry but the approach is too naive and the tech isnt there yet.
You can't make up a couple of conversation topics and expect the LLMs to do the rest by just switching languages. People approach the same topics completely different in different languages. The app looks like someone picked a couple of topics and the rest is "just" ChatGPT advanced voice mode.
And the worst thing is that the LLMs in TTS do not sound native and cannot teach you pronounciation and learning to listen and understand (which is the whole point in having spoken conversation).
And the other way around, the STT will not notice pronounciation mistakes made by the student - so the app cannot tell you: oh, its pronounced like this.
Congratulations on a successful launch. Wishing you success.
Honestly tried it out, I wanted to like it but in its current form I found myself frustrated enough to just end the 'call' and close the app. Been learning Spanish for quite some time now so wasn't put off by the 'it always talks in X language' thing people are talking about.
The thing that put me off was the speech recognition. I am not in a loud environment and I wasn't even talking and it was picking up responses and responding to it before I even opened my mouth. It blazed through the 'preferences' set up itself making up responses. Then when I did get to talk it just simply got my answers wrong. It would often interject too at random during my sentences.
I tried the app. I love that you’re tackling this and I’m rooting for you. I’ll tell you about myself, my experience, and my thoughts.
I’m currently learning French as a beginner and I’ve learned other languages in the past. I’ve trued Duolingo as well as italki and frantasic as well as just ChatGPT. I am very familiar with Anki and I think it’s critical to make your own flashcards by choosing images and sounds. I don’t want auto cards.
My experience with Issen:
* it’s frustrating when the conversation partner doesn’t remember what it just said - it means I can’t get a chance to ask que c’est que ça veut dire.
* it’s frustrating (just like with ChatGPT) that the conversation partner tends to interrupt and jump in while I’m thinking. I think many learners speak slowly and spend extra time thinking. ChatGPT allows you to hold the glowing circle and it won’t interrupt while you do.
I’d love to see the chat bubbles have more in depth features like:
* much clearer indicator of hover or click words for translation, and more features like example sentences or click to pronounce
* an option to ask for an explanation of some or all the text
* for my own text I’d love to see feedback with more UI native elements about how accurately I pronounced each word and any grammatical mistakes I made. The text summary is a great start
I found myself ignoring the features of the chat bubbles and only in writing this feedback did I notice them! They could maybe use more contrast and clear UI emphasis. Duolingo does a good job of making their UI very clear with this kind of feedback.
I think it’s important to build features that augment the app to work around LLM limitations. My guess is a lot of the settings change the prompt and that’s great but I think it leaves too much room for hallucinations to nosedive the experience.
I’d also love to see some way to have a hold to talk or something similar.
I’m very conscious at this point about the cost of these lessons and I have a hard time finding the price. Frantastic is absurdly expensive and it made me switch to italki where human conversation is literally cheaper. Without differentiating more from ChatGPT I would have a hard time justifying an additional subscription to my wife!
Edit: I found the pricing and it’s a tough sell! ChatGPT is cheaper.
I think you can both differentiate further from ChatGPT and keep cost down. I’d recommend to try to get more value out of each API call, so learners are more aligned with the cost per interaction- like make it so I’m enticed to spend a little longer reviewing the chat bubbles. My suggestions are mostly about how I want more engagement with each utterance anyway. Right now it’s very tempting to just keep making more and more utterances and IMHO that drives up costs while being frustrating for me.
I’d be happy to discuss! I wish you success.
You have Catalan and Galician but not Basque
I've been waiting for someone to build this! Trying it out now
tried it in Safari, didn't hear anything of the intro sentence after choosing a voice and then i got
"Error An unknown error has occurred."
has this been tested on Safari?
Someday someone will release a good AI based language learning app, because it’s the obvious use of the technology.
That person will have a hellish time marketing it because projects like this will have so thoroughly primed us to assume its slop.
THIS IS AMAZING!
I tried using this to learn some basics of Mandarin Chinese. It was frankly a disastrous UX. I have no idea how to begin a useful lesson, the AI just started talking at me in full on Mandarin and asked me questions in Mandarin. How am I supposed to engage with this as a complete beginner?
The text generation and speed of speech also seems painfully slow at this time.
Great work! I'm learning Spanish in Argentina, and most of the apps that offer it just have Mexican or Spain variants of the language. I think it's the first time I see a selection of different virtual tutors with regional dialects.
this is the future of language learning. love that you guys are working on this. gonna try it out for Indonesian this weekend :)