Google has opened its Google Voice telecommunications service to anyone in the United States interested in using a single telephone number for all of their phones. Over a year ago, Google released an early preview of Google Voice, a web-based platform for managing communications. The company introduced one number to ring a users' phones, voicemail that works like email, free calls and text messages to the U.S. and Canada, low-priced international calls and more. However, users had to request and receive an invitation to try it out.

Today, Google open up Google Voice to the public, no invitation required.

Along with letting users have one phone number that rings at all of their telephones, the service converts voice mail or text messages into email and allows for toll-free calls to the United States and Canada.

Google promised "less annoyances and more awesomeness -- for free."

People in the United States can sign up for the service online at google.com/voice.

Google promises that the service works "no matter what kind of phone you have or which carrier you use."

Last year, Google also introduced a mobile web app, an integrated voicemail player in Gmail, the ability to use Google Voice with an existing number and more. Over a million of users are now actively using Google Voice, Google said.