Terros Digital
Now on the App Store

Purposeful apps
for serious learners.

We build depth-first tools for people who want to genuinely master hard skills — starting with Mandarin Chinese.

Browse appsLearn about Menzi

Featured App

Menzi

Mandarin Chinese for iOS — serious learning, serious tools.

iOSAvailable
Hanzi Mode

See a character, type the pinyin. Builds the reading-to-pronunciation link most apps skip.

Pinyin Mode

See pinyin, write a sentence. Forces active production — not just passive recognition.

Learn Mode

New words arrive with AI-generated explanations and example sentences before entering your queue.

Speaking Mode

Real-time voice conversation with an AI tutor constrained to your vocabulary — no unfamiliar words.

Listening Mode

Comprehensible input sentences generated from your own deck, read aloud at exactly your level.

Constructs Mode

Grammar pattern library with AI-graded sentence construction exercises, tracked per pattern.

Full app details

App Preview

See every mode in action

Dashboard

Dashboard

Everything due at a glance

Speaking Mode

Speaking Mode

Real-time AI conversation

Listening Mode

Listening Mode

Comprehensible input, scored by AI

Learn Mode

Learn Mode

AI-generated explanations and examples

Hanzi Mode

Hanzi Mode

Character → pinyin recall

Pinyin Mode

Pinyin Mode

Sentence construction with AI feedback

Constructs Mode

Constructs Mode

Grammar pattern drills, graded by AI

Approach

Why it works

SM-2 spaced repetition

The classic algorithm schedules every card at the exact right interval — reviews compound, never pile up.

AI-personalized practice

Every LLM interaction is shaped by your vocabulary deck and performance data, so feedback is always relevant.

Efficient review sessions

Cards are scored 1–5 with natural language feedback. Spend your time on what you actually need to drill.

Vocabulary-constrained AI

Speaking and Listening modes stay within your known words — comprehensible input at your level, always.

Start learning Mandarin today

Download Menzi on iOS and build a vocabulary that actually sticks.

Download on the App Store