Google Voice - Just one powerful number

The service is configured and maintained by the user in a web-based application, styled after Google's e-mail service, Gmail, or through the service's Android and iOS apps. Google Voice currently provides free PC-to-phone calling within North America, and PC-to-PC voice and video calling worldwide between users of the Google Voice and Video Chat browser plugin (available for Windows, Intel-based Mac OS X, and Linux).

Many other Google Voice services—such as voicemail, free text messaging, call history, conference calling, call screening, blocking of unwanted calls, and voice transcription to text of voicemail messages—are also available to users resident in the US. Transcribed and audio voicemails, missed call notifications, and/or text messages can optionally be forwarded to an email account of the user's choice. Additionally, text messages can be sent and received via the familiar email or IM interface by reading and writing text messages in Gmail or in one of the Google Voice Apps that are available for Windows, Android and iOS