LittleSnitch

Used by 827 people for 419 hours, 56 minutes and 17 seconds

Little Snitch tells you when a program tries to send info to the internet. If you do not like the idea of information possibly being gathered from your computer and being sent to who-knows-where for who-knows-what, Little Snitch helps. When an application tries to establish a network connection, Little Snitch intercepts the attempt and brings up an alert panel giving you all the connection details including the name of the application, which initiated the connection. You either choose to allow the connection, to deny it or to add a permanent rule for similar future connections.

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