On-device AI · iPhone 15 Pro+

Your private
language tutor

Practice any language with an AI tutor that runs entirely on your iPhone. Your voice, your mistakes, and your progress never leave your device.

Download on App Store FAQ
Spanish · intermediate
Español
Day 42 · 14-day streak
Today's phrase
No estoy seguro de lo que quiero.
I'm not sure what I want.
You said
No estoy seguro de que yo quiero.
Tutor feedback
Good effort. Drop "yo" — it's implied by the verb. "De lo que quiero" flows more naturally.
Voice stays
on device
How it works

Learn naturally,
progress privately

No subscription traps, no gamification gimmicks. Just real language practice with an AI that adapts to how you actually speak.

01

Pick your language

Choose your target language and proficiency level. Lingu calibrates to where you are today, not where a curriculum says you should be.

02

Speak and get corrected

Practice sentences, conversations, and pronunciation. The AI gives you direct, actionable feedback — not just "good job."

03

Build real fluency

Lingu tracks your weak points and surfaces them again until they stick. Progress is measured by what you can actually say.

Features

A tutor that knows
exactly where you are

No one-size-fits-all lessons. No cloud processing your pronunciation. Just an AI that adapts to you, privately.

🧠

On-device AI tutor

Apple's MLX framework runs the language model on your A17 Pro chip or newer. Your voice never leaves the device — not even for transcription.

📚

Adaptive proficiency memory

Lingu remembers your vocabulary gaps, recurring grammar mistakes, and learning rhythm — and adjusts every session around them.

🌍

Offline travel mode

Download your language pack (~1–2 GB) and use Lingu anywhere — no roaming, no Wi-Fi, no data charges abroad.

🔊

Direct feedback, no sugar-coating

The tutor corrects your grammar and pronunciation with precision. You learn faster when feedback is honest, not encouraging.

Privacy

Your voice is
yours alone

Every other language app processes your voice in the cloud. Lingu processes everything on your device. Your pronunciation data, your mistakes, your progress — none of it goes anywhere.

Read the privacy policy
On device
AI model & language inference
On device
Voice & pronunciation analysis
On device
Learning progress & history
On device
Vocabulary & grammar tracking
Never sent
Voice recordings to any server
Never sent
Learning data or analytics
Never sent
Account or identity info
Pricing

Free. Completely.

Every language, every lesson, every feature — included from day one. No paywall, no trial period, no upsell.

Get 01Lingu for free