Competitions and gamification
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Baidu (百度)
Search engine and news
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The touch point on the top right of the home page takes you to a list of competitions.
Each competition is almost its own mini app. Some require you to play a mini game, some make you invite as many friends as possible and compete on a leaderboard, some make you do tasks, some are a lucky draw and so on. You can win money, electronics, mobile data, and so on
Some of them have multiple editions and run for weeks, some are special promotions.