When you try to open an app you downloaded from a source other than the Mac App Store sometimes you may get the popup below, preventing the app the from opening.
You’ll need to override the security settings to open the app, the following steps will show you how:
1. Navigate to folder the Callinize application is installed at and Ctrl+click or right click on the app and select Open from the menu.
2. This time you’ll see the popup below instead of a message saying the app can’t be opened at all. Click Open.
That’s all! The app will open normally from this point on without having to go through these steps again.