Ka: The fun way to master Chinese tones

Ka is an iOS app that helps people learning Chinese properly recognize and use the tones found in the language.

Mandarin Chinese is notoriously difficult to learn because it is a tonal language. Unlike English, the same syllable can have a totally different meaning based on the pitch used to pronounce it. For example, ma could mean either mother or horse — and it’s certainly important to not confuse your mother (mā) for a horse (mǎ)!

Ka makes learning Chinese tones easy and fun. It contains thousands of quick, snappy drills across 6 stages and 80 levels that help learners identify and tell apart similar tones. Each level introduces different words and their corresponding tones, and quizzes learners on their understanding. The experience is designed to be as intuitive as possible; it simply consists of cards that can be swiped either left or right. The word “Ka” means “card” in Chinese.

As learners advance, they collect stars, unlock collectibles and build a daily streak. These gamification elements help reduce the cognitive load and stress for non-native speakers trying to master Chinese tones.

Ka is available for iPhone and iPad. It is suitable for beginner and intermediate learners of Chinese.

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App Store URL

What’s special about Ka?

It focuses on a very specific language-learning problem: mastering the tones in Mandarin Chinese.

It is designed to be as fun and engaging as possible.

Each level takes just 2 to 3 minutes to complete.

All of the content can be accessed for free.

The engineer who created Ka formerly helped build Duolingo as its first-ever associate product manager.


Ka is free to use, with an optional in-app purchase.

Learners start off with 5 lives, and lose 1 every time they get a card wrong. Each life takes 2 hours to regenerate.

Unlimited lives can be unlocked with a one-time US$4.99 in-app purchase. The purchase also removes ads and provides full offline access to the app.

About the developer

Kai Loh is an independent software developer from Singapore. He is currently based in Seattle.

Kai joined Duolingo in its early days and was its first-ever associate product manager in 2015.

In 2018, he established Duolingo’s first office outside the US in Beijing, China, where he served as General Manager.

Before leaving Duolingo in 2022, he was Senior Director of Product Management, where he led efforts to grow Duolingo’s user base.

Prior to Duolingo, Kai was a Program Manager at Microsoft. He holds a Bachelor of Science in Computer Science-Economics from Brown University.

Contact email: kai@autographlabs.com

App logo & screenshots

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App download URL