To turn off Landscape support ...

  1. Go to the project's build, deployment, resource etc settings by clicking on the project's root in Xcode's Project Navigator window.
  2. Under the Project section, select the iOS target instance of the app.
  3. Select the General tab (if it's not already on that)
  4. Under the General tab's Deployment Info section, adjust the supported Device Orientations as needed, i.e. uncheck the Landscape options.

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