AI-Powered ESL Training · 52 Languages

Learn English The Smart Way

AI-driven translation exercises, grammar correction, and pronunciation coaching - designed for real ESL learners worldwide.

Poly-Puff mascot
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1500+
Grammar Rules
52
Languages Supported
18
Learning Modules
100%
Rule-Based Grading

Built Different

Not just another flashcard app. Real grammar intelligence, real-time feedback.

Database-First AI

1500 grammar rules are checked before any AI call. Hard rules always win - "a university" is always correct, no matter what the model thinks.

Accuracy Heatmap

Visual progress rings transition from red to emerald as your score improves. See exactly where you stand on every exercise.

Dual Audio Feedback

Hear the native-speaker version at 0.9× speed for clarity, then hear your own translation played back to spot flow issues.

Global Compliance

GDPR, COPPA, POPIA, Egypt PDPL, LGPD - smart age gates and parental consent flows for every jurisdiction.

Instant Correction

Tap any underlined error to see the exact grammar rule that applies. No vague feedback - specific, citable corrections.

Classroom Mode

Teachers can assign exercises, track class progress, and set daily challenges - built for real ESL classrooms.

All Web App Modules

Every aspect of language learning, covered.

Module overview

Translation Trainer

Your Language, Your Way

Grammar feedback supports 52 native languages. Website language options stay limited to reviewed translations.

The name

What Poly-Puff Means

Poly comes from the Greek polys, meaning many. Puff suggests a small, soft cloud, like an internet cloud for language practice. Together, Poly-Puff means many languages and ideas gathered in one light place to learn.

Poly from Greek polys: many, much, or more than one.
Puff a soft breath or little cloud, a nod to learning online in the cloud.

Start Learning Today

Download the app - free to start.

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QR code for Poly-Puff on Google Play
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Silent video showing the Poly-Puff practice hub, translation feedback and progress tracking alongside illustrative footage of people using phones.