LINA
Bilingual AI Learning & Note Studio (EN · 中文)
Learning across two languages at once is a tab-juggling nightmare. You bounce between a tutor in one window, your scattered notes in another, and a dictionary in a third — and none of them know anything about each other. LINA (智能学习助手, 'intelligent learning assistant') collapses that into one bilingual surface where the tutor and your notes finally share a brain.
Origin Story
LINA grew out of my own bilingual study — English and Mandarin — and the realisation that the friction was never the lessons themselves, it was the connective tissue. The notes you take while learning are the most valuable artefact you produce, and yet most apps treat them as a dead-end text box. I wanted a system where conversation and note-taking were one continuous loop.
How It's Built
The core design bet was real-time. Conversations stream in over a persistent connection so the tutor feels immediate rather than request-and-wait, and the note system sits alongside it so anything worth keeping is one gesture away from being captured, organised and revisited.
Engineering Notes
Real-time over a socket
Conversations stream token-by-token over a persistent connection rather than request-and-wait, with reconnection handled so a dropped link doesn't lose your place. It's the difference between a tutor that feels present and one that feels like a form submission.
Notes as first-class data
The notes you take while learning are the most valuable artefact you produce, so LINA stores them as structured, searchable records — across both English and Mandarin — rather than a dead-end text box. The tutor and the notebook are aware of each other; study and capture are one loop.
LINA treats your notes as the point, not the by-product. The most durable thing you build while learning a language is your own structured record of it — so the assistant and the notebook should be the same object, talking to each other in real time.
What It Does
Bilingual by Design
English and Mandarin are first-class throughout the interface — not a translation layer bolted onto an English app, but a genuinely dual-language study environment.
Real-Time Tutor
Conversational tutoring streams over a persistent connection, so guidance arrives token by token and the exchange feels live rather than transactional.
Note Management
Capture, organise and revisit study notes alongside your lessons. The notes are part of the learning loop, not an afterthought — searchable and structured for review.
Secure Sign-In
Google single sign-on keeps your study space and notes private to you across devices.
Where It Stands
LINA is deployed with bilingual English/Mandarin study and a real-time tutor. Because notes are first-class structured data, the next moves — spaced review and additional language pairs — extend the same loop rather than bolt on a new one.
LINA is a Next.js and TypeScript application with Tailwind CSS, designed around a real-time connection that streams the assistant's responses rather than polling for them. The language model is Gemini, and Firebase provides authentication (Google sign-in) and persistence for the bilingual note system. The architecture is built so that the tutor and the note store are aware of one another — study and capture are a single continuous flow rather than two disconnected tools.