Windows
Go to the task-bar icon on windows and right click then select "new identity" RightRight click the onion icon in Windows Notification Area, and Select "New Identity".
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Android
Go to the Orbot app, and on the big power icon swipe horizontally.
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Ubuntu
Go to your vidila control panel and hitClick the silhouette which says change identityonion icon in Tor browser, and Select "New Identity".