For certain activities, you unlock Achievement Badges. Some of these are Inner Circle, Sharpshooter, Big Spender, Overachiever, Overtime, Friendlt, Wildfire and Champion.

Each badge has 3 levels that you progressively unlock.

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Duolingo

Duolingo Clubs
Gamification: Streak, Lives and Gems
Change or add language
Learning experience
Asking for notiification permissions during onboarding
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Duolingo Plus
Gamification memes
App icon change
2019 redesign
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Gamification

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Gamification
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