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Normally, when Facebook users receive a new message and open it, a report is sent to the sender informing them that the message was read with the time display as well.
But iPhone users today can experience a new free application, NoSeen for Facebook, to prevent a "View" or Vu report from appearing after opening and reading messages.
The application also allows users of iPhone phones to respond to messages as well as the possibility to browse without a report "View", and can be downloaded from the App store.
hi @abouche.youness, that's a good explanation, but if you perfects it will be great