Download of blackvpn 3.7 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. Blackvpn for Mac lies within Security Tools, more precisely Personal Security. The actual developer of this Mac application is Blackvpn. We recommend checking the downloaded files with any free antivirus.
From the developer:
blackVPN protects your privacy and prevents your ISP, government or employer from monitoring and controlling your online communications and browsing activity. Prevent websites from using your IP address to identify you or your location. The location of the IP address you will get on the Internet depends on which server you connect to.
You may want to check out more Mac applications, such as Key Holder or PasswordVault Lite, which might be related to blackvpn.