←back to thread

Launch HN: Issen (YC F24) – Personal AI language tutor

313 points mariano54 | 2 comments | 26 Jun 25 14:32 UTC | HN request time: 0.463s | source

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!

1. dbuxton ◴[26 Jun 25 19:51 UTC] No.44390650[source]▶
For me this is great for practice (I tried Russian). However the big missing piece for all these language learning apps is the lack of support for spotting and correcting errors in your pronunciation - as long as you say the word more or less right, the transcription gives you a pass.

I am very excited for the whole STT/TTS to go away and for us to have models that really "hear" exactly what you said.

Sometimes this is about accent but a lot of the time, the AI won't spot areas where you e.g. fudge a case ending or the stress on a word. Yes, you can get some of that pronunciation right by the AI repeating back with the correct stress or clear case, but you never really get the confidence that you would get from an actual human.

Another product suggestion - turn off transcription (at least for the tutor side of the conversation; I'd suggest both). Personally I find it distracting at best for languages I already speak well and a crutch for those I don't.

Finally, I find it really very hard to enjoy having a random conversation that's not very directed ("What interests you most about artificial intelligence?"). I'd suggest that there are ways of making it more goal focused without being explicitly gamified - maybe something like, here's a position and you have to persuade me (AI debate club!), or something that brings out an actual opinion or relates to a concrete experience ("what's your main goal in your job this year").

Overall though this is the first product I've seen in this space that I might actually use, so well done.

replies(1): >>44391081 #
2. mariano54 ◴[26 Jun 25 20:38 UTC] No.44391081[source]▶
The persuasion lesson sounds like a great idea, we haven't thought of that. Yeah voice to voice models will be amazing. There is significant progress from openai/gemini, and we plan to use them when they are ready.