With Troops, you can create Action Buttons that let you call Salesforce contact(s).
Here's how to run those calls through your preferred dialer or service:
Note: In order to open with your dialer, you need to have the desktop App for the given dialer installed.
If you use a Mac...
Go to FaceTime Preferences
In the Settings panel, select your dialer app in Default for calls, as shown below:
Close the panel and close FaceTime