Katchi
Redefining Language Exchange Through Structure, Safety, & AI
Katchi (meaning together in Korean) is a purpose-driven language exchange platform for serious learners, where every conversation gets you one step closer to mastering the language. Unlike existing language exchange apps today that do little to facilitate conversations, Katchi helps learners build consistent, prompt-based practice in a safe environment.
① Problem Statement & Goals
Language exchange apps that don't actually teach
Most language exchange apps promise conversation, but fail to deliver productive learning. They attract users seeking casual conversation rather than committed practice, leading to:
- Unstructured, unfocused conversations that don't support real language growth
- Partners with mismatched intentions and inconsistent goals
- Unsafe or uncomfortable behavior that discourages serious learners
While existing language exchange apps like HelloTalk and Tandem are feature-rich, these environments do not facilitate productive learning.
After spending 9 months studying in Seoul and feeling frustrated by my attempts to learn Korean through language exchange, I set out to design an app that facilitated productive learning and connected serious language learners.
Design Challenge: How do we create a platform that encourages sustained learning, facilitates matches based on genuine study goals, and facilitates productive language learning?
② Defining the Product Vision
Serious learning needs serious structure
Katchi is positioned as a purpose-driven language exchange platform, for serious learners who want structured practice, real feedback, and safe, goal-based connections. Our focus is on quality over quantity of interactions and treating conversation as a study method, not merely a social hobby.
Katchi blends design, AI, and behavioral psychology to build a structured and safe ecosystem for sustained learning.
Core Principles
- 01. AI-powered learning — transforming every chat into productive learning sessions
- 02. Goal-aligned exchange — matching learners by intent, proficiency, and study focus
- 03. Safety-first matching — ensuring comfort, respect, and commitment to real learning
③ AI as the Learning Companion
AI that coaches without taking over
AI sits at the center of Katchi's learning experience by enhancing conversation, not replacing it.
Core Capabilities
- 01. Goal-Aligned Partner Matching
- 02. AI-Driven Conversation Prompts
- 03. AI-Powered Post Session Recap
④ Design Process
From casual conversation to deliberate practice
Capability 01
Goal-Aligned Partner Matching
Most language exchange apps struggle with mismatched expectations — one partner wants structured practice while the other just wants to chat. Katchi solves this by matching users based on intent, learning style, and study goals.
How it works
Onboarding captures intent
Learners share their goals, preferred correction style, speaking ratio, and session structure.
AI matches by motivation
Katchi's AI recommends partners who are equally motivated and aligned in how they want to learn.
Prep Summary before every call
Shared goals and suggested topics so both partners enter each session with clarity and purpose.
Result: More compatible matches for practice sessions that feel productive from the start.
Capability 02
AI-Driven Conversation Prompts
Many language learners struggle to keep conversations flowing when speaking with a partner. Katchi's AI prompt assistant acts as an in-session study coach, guiding practice with structured prompts and intelligent feedback so users can focus on speaking, not planning.
Contextual Prompts on Demand
Grammar-Based Prompts
Practice the exact grammar patterns they're studying
Situational Prompts
Restaurant, travel, job interview, and other real-life scenarios
Recent Vocabulary
Instantly bring previously saved words back into the conversation
General AI Suggestions
Topic ideas, follow-up questions, or phrasing help
Real-Time AI Coaching
Conversation flows
AI listens passively to the exchange in the background
AI detects an opening
A grammar error, missed pattern, or chance to expand naturally
A small tooltip surfaces
Unobtrusive, non-disruptive, and fully user-driven
Correction card opens
A correction, example sentence, and optional quick practice prompt
Capability 03
Post-Session AI Recap
Katchi transforms each conversation into study material you can immediately learn from. After every session, learners receive an AI-generated wrap-up designed to reinforce progress and highlight growth areas.
The recap includes
Full transcript & audio replay
A searchable transcript with speaker labels and timestamps, plus access to the session recording.
AI Summary
Grammar accuracy, vocabulary usage, fluency improvements, key metrics, new words, and corrections — all extracted automatically from the session.
AI-generated insights
Metrics, vocabulary highlights, and grammar corrections, all automatically extracted and saved for review.
⑤ Key Results
A hybrid skillset on display
Katchi demonstrates how AI can amplify human potential rather than replace existing processes. By acting as a conversation coach, the AI guides learners to focus on meaningful practice without taking over the human connection at the core of learning.
This project highlights my hybrid skillset: the ability to identify a real user problem, define market-differentiating functionality, and translate that into features that drive engagement and retention, all while delivering beautiful, usable design. Even in a personal project without live data, Katchi allowed me to explore the full spectrum of product thinking and design execution — from concept validation to interaction design, demonstrating how thoughtful AI integration can enhance both experience and outcomes.