The top level tabs have roughly stayed the same while the visual style has been tweaked to be cleaner and the owl has been redrawn.

The Clubs feature is being A/B tested against the Leaderboards tab (and some users aren't happy about it: Petition to save Clubs)

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Duolingo

Learning experience
Create profile
Gamification: Streak, Lives and Gems
Onboarding
Top level tabs
Gamification memes
Duolingo Clubs
Asking for notiification permissions during onboarding
Duolingo Plus
App Store screenshots
App icon change
Gamification: Badges
Change or add language

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Content Screens

Setup Tab
Restaurant page
Top Level Tabs
Top level tabs