As mentioned above, Google's new Windows app is currently being tested as a Labs experiment and isn't widely available yet.

Managing calls, texts, and voicemails across multiple devices can quickly become overwhelming, especially when juggling personal and professional communication. Have you ever wished for a single, ...

Google Voice is a voice-calling and text messaging application. It provides you with a phone number, making it simple to separate your lines. The app is free for personal use in the United States.