Little Snitch

A firewall can protect your computer from unwanted visitors coming in from the Internet. But who protects your private data from being sent out? Little Snitch does! Once connected to the internet, applications can send any information they want to wherever they please. Sometimes they do this for good reasons, at 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. Whenever a program tries to establish an outgoing internet connection, Little Snitch alerts you. You can then choose to allow or deny the connection, or define rules for how to handle similar attempts in the future. This reliably prevents private data from being sent out without your knowledge. Little Snitch runs unobtrusively in the background and can also detect network-related activities of viruses, trojans, and other malware. Note: Pricing is based on purchasing or upgrading a single license as of October 10, 2017—discounts are available for multiple licenses.

Little Snitch is a firewall application that monitors and controls outbound internet traffic on Mac computers, protecting user privacy and preventing unauthorized transmission of private data.