Build a Language Learning App Like Duolingo in SwiftUI

A language learning app like Duolingo is, underneath, a path of short exercises plus a spaced-repetition engine that decides what to review and when. The polish is in the loop: quick wins, gentle correction, and a streak that encourages without punishing. VP0 is the free, AI-readable iOS design library builders start from for these screens, so you can focus on the learning mechanic rather than designing lesson cards from scratch.

Who this is for

You are building an education or language app in SwiftUI, perhaps with Cursor or Claude Code, and you want the proven learning loop without copying anyone’s brand. This is the pattern.

Learn the pattern, never copy the brand

It is fine to study a well-known app and build the same mechanic; it is not fine to copy its identity. Build your learning app with original lessons, your own brand and mascot, and audio you have licensed, and never reuse Duolingo’s name, characters, or course content. About 76% of developers now use or plan to use AI tools to build apps like this, which makes original, well-structured content the thing that actually sets yours apart.

The exercise types

A good course mixes a few exercise shapes so practice stays varied and tests different skills.

Exercise type	What it tests	SwiftUI approach
Multiple choice	Recognition	A grid of tappable option cards
Type the answer	Recall and spelling	A text field with gentle validation
Listen and repeat	Listening and pronunciation	AVFAudio playback plus a replay button
Match pairs	Vocabulary links	A two-column tap-to-pair board

Render the visual side with SwiftUI, play pronunciation with AVFAudio, and keep targets large and legible per Apple’s Human Interface Guidelines. Always pair audio with text so an exercise still works with sound off.

Spaced repetition and forgiving streaks

The engine that makes daily practice add up is spaced repetition: store a difficulty and a next-review date per item, surface due items first, and push easy ones further out. Pair it with a streak that forgives a missed day rather than resetting to zero, the same kind, low-guilt design behind an ADHD routine planner and a Duolingo-style streak flame animation. A brittle streak drives people away; a forgiving one keeps them coming back.

A worked example: one lesson

Walk through a single lesson. The learner opens today’s path node and sees five short exercises. The first is multiple choice: a word with four tappable option cards and instant feedback on tap. The second asks them to type the translation, with forgiving validation that accepts a minor typo rather than punishing it. The third plays a short clip and asks them to pick what they heard, audio paired with text so it still works with sound off. The fourth matches pairs, and the fifth is a quick recall of a word seen days ago.

As they answer, the spaced-repetition engine quietly updates each word’s difficulty and its next-review date, so the word they just fumbled returns tomorrow while the one they nailed comes back in a week. At the end they see progress, not a harsh score, and a streak that survives the occasional missed day. The whole lesson takes about two minutes, and the engine is what makes those two minutes compound over weeks into real vocabulary. That loop, short and kind and scheduled, is the entire product, and it is also why original, well-paced content matters more than any single screen. The first ten lessons are where most learners quit, so invest your best content and clearest feedback there, and let the spaced-repetition schedule quietly carry the long tail.

Common mistakes and fixes

• Copying course content. Write your own lessons and license your audio.
• Audio-only exercises. Pair every clip with text for sound-off use.
• Re-studying everything equally. Schedule reviews with spaced repetition.
• Punishing a missed day. Forgive streaks instead of resetting them.
• Cramming too many types in one lesson. Keep each lesson short and focused.

Links from email or a share sheet should open the right lesson, which is exactly the deep linking and unhandled URL problem handled well. When you are ready to scan tickets or codes, the same care carries into a QR ticket scanner.

Key takeaways

• Build the lesson-path mechanic; write your own content and license audio.
• Mix exercise types and always pair audio with text.
• Spaced repetition is the engine that makes daily practice efficient.
• Keep streaks forgiving, and start from a free VP0 SwiftUI design.

Frequently asked questions

The FAQ above answers how to build the app, whether you can clone Duolingo, what spaced repetition is, and how to play pronunciation audio in SwiftUI.