Name: Little Snitch
Mac Platform: Intel
OS version: 10.8 or higher
Fixed a bug which caused a kernel panic on some OS X 10.11 El Capitan installations
Fixed a bug related to iOS Simulator apps where tvOS apps in the simulator would not show connection alerts and would lead to a crash in Little Snitch Configuration and Network Monitor
Fixed a bug which caused Until Quit rules to remain active after quitting the related application
Courtesy of TNT Team
Little Snitch... A firewall protects your computer against unwanted guests from the Internet. But who protects your private data from being sent out? Little Snitch does!
As soon as you're connected to the Internet, applications can potentially send whatever information they want to wherever they want.
Sometimes they do this for good reason, on your explicit request. But often they don't. Little Snitch allows you to intercept these unwanted connection attempts, and lets you decide how to proceed.
Little Snitch informs you whenever a program attempts to establish an outgoing Internet connection. You can then choose to allow or deny this connection, or define a rule how to handle similar, future connection attempts. This reliably prevents private data from being sent out without your knowledge. Little Snitch runs inconspicuously in the background and it can also detect network related activity of viruses, trojans and other malware.
More info: http://www.obdev.at/products/littlesnitch/index.html