Redpen

An AI English speaking tutor for iPhone.

Your words.
A clearer sentence.

Say a sentence. See the mistakes it finds.
Understand the rule. Say it again.

See a practice round
Download on the App StoreComing soon to the App Store
Get it on Google PlayComing soon

$4.99/week · 3-day free trial for eligible users.
AI can make mistakes.

Real Redpen example: Yesterday I go to the office and meet my team. Go becomes went; meet becomes met.
From the app · example sentence

A sentence.
A rule. Another try.

Speak and confirm. Understand the rule. Repeat the correction. Start with something you actually want to say.

Redpen review screen showing red grammar corrections and the Past simple explanation.

Speak. Then understand.

Confirm your transcript. See the marked words and the grammar rule behind the correction.

Redpen drill screen for repeating a corrected sentence.

Say the correction.

Practise the corrected sentence aloud. The drill checks the words you repeat, not pronunciation.

Redpen Notebook grouping saved mistakes by grammar rule.

Keep the rule.

Your Notebook groups saved mistakes by rule, ready for another practice round.

Explanations in Spanish and Vietnamese.
English explanations for everyone else.

Your practice.
$4.99 a week.

Start with 3 days free.

For eligible users. Then $4.99/week.
Corrections, rule explanations, sentence drills and your Notebook, in one subscription.

See store availability ↑

Apple bills your subscription. Payment is charged to your Apple Account at confirmation or when your trial ends. It renews automatically unless cancelled at least 24 hours before the current period ends.

Manage or cancel in Apple Settings. Deleting the app or your account does not cancel billing. Local price and trial eligibility appear in the app.

Manage an Apple subscription ↗

A few clear answers.

Is Redpen an AI tutor?

Yes. Redpen is an AI English speaking tutor app, not a human teacher. It marks possible grammar mistakes and explains the rule. AI can make mistakes.

Who is it for?

Adult English learners whose first language is Spanish, Brazilian Portuguese, Japanese, Korean, Vietnamese or Turkish. Grammar explanations are available in Spanish and Vietnamese. Other native languages receive English explanations. English is available to everyone.

What happens to my voice and words?

Audio stays on your phone. Only the transcript you review and confirm is sent for correction, after your consent. Unsaved transcripts expire after 30 days. Saved Notebook entries stay until you delete them. You can delete your account anytime.

Does it assess pronunciation?

The drill checks whether you repeat the corrected words. It does not assess pronunciation.

How do the trial and subscription work?

Eligible users get a 3-day free trial, then pay $4.99 per week. Apple bills the subscription, which renews automatically unless cancelled at least 24 hours before the current period ends. Manage or cancel in Apple Settings. Deleting the app or your account does not cancel the subscription. Local price and eligibility appear in the app.

Can I download it now?

Redpen for iPhone is in App Review. The App Store listing is coming soon. Google Play is coming soon. Use the store badges above for available downloads.