Love this App - In-Call Dialing Does Work!

In call dialing does work. Once you connect the call, just use the numbers / keypad on your computer’s keyboard. What’s happening is that once the call is made, the app seems to switch to Facetime. You won’t hear the tones when you press the keys on your keyboard, but the prompt or entry will be recognized. If you try using the app’s keypad interface on the screen instead, you’ll hear the tones, but nothing happens. A bit confusing, but it works using the keyboard nonetheless. IMHO the app is still very useable and a great productivity booster.

Robert Maizner about Keypad