If you forgot to log out of a public computer, misplaced your device, or suspect an unauthorized log in, the first step is to log out of all devices. Twitter, like any other social networking app, allows you to log out of all devices or sessions where you are currently logged in. Following is the process for the web app, which means that the mobile apps could be a bit different.
1) In the left pane, click the More icon (three dots) to access more menu options.
2) Click Settings and Privacy to open options related to signing in.
3) In Settings, click Account.
4) In the right pane, under Data and Permissions, click Apps and Sessions.
5) Under the Sessions section, click Log out of all the sessions.
6) Click Log out to confirm the action.