What is that white line at the bottom of iPhone screens used for?

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But Jefferson Duke, aka “Big Duke” on TikTok (@bigduke13entertainment), has a special hack that he claims all iPhone users should be employing.

In a TikTok with over 2.1 million views, Duke demonstrated how the line at the bottom of an iPhone exists to take the user back to whatever app they had been using previously — in order. Click the line, and you’re automatically transferred back to your previous open app.

“Why do you think iPhone created this line?” Duke asked. “Man, if you screaming team iPhone, you better know how to do that.”

Plenty of iPhone users, however, admitted that they didn’t know how to do that, including lifestyle influencer Toirajnai (@toirajnai), who posted a duet with Big Duke expressing her shock and awe.

“All these years and aint nobody tell me nothing!” Toirajnai captioned her video, which has received over 1.1 million views.