PIA: please register your client app for Mac with Apple
For whatever reason, PIA does not care enough about Apple customer base to even register their client app with Apple. As a result, on any Mac with even the lowest security settings, the OS X will block the installation since the app comes from an "unidentified developer". We are not talking here about the app certification for distribution through the Apple's App Store - just the developer/app registration.
To install the downloaded PIA client app, user has to circumvent his own base security settings - highly unprofessional treatment of PIA's customers on Mac!
The fact that PIA does not want to bother even with registering their software with Apple, which is fairly straightforward and simple (unlike the certification by Apple), is a clear indication that support for Apple customers is not a priority. That's why iOS has yet to be fully supported, and why Mac users have all kinds of problems with PIA service with virtually no help from the dismal PIA support. To grasp the depth of this problem one just needs to browse the forums.
Is it really too much to expect from a paid-for service such as PIA to register its client app for Mac with Apple?