I think this application will be very useful and easy as it can help with various things. For example i would imagine it could help people understand other people who do not speak english as they can use the google voice to translate a word or sentence that they do not know. :)

"The transcription is the best new feature. It transcribes every voice message into text and lists them on a page where you can read them all. The Google Voice dashboard page is integrated with your other Google apps and is accessible through your Gmail account, just like your other apps. You can choose a whole range of options in your settings: You can have the voice messages forwarded to your phone in the form of an SMS, so that you have everything on your mobile phone — you can click to listen to the original message or see the message transcribed. You can choose what exact hours a particular person can reach you at, say, your home number, and what hours they’re transferred to your cell, or directed
immediately to voice mail."

Some of the disadvantages of 'Google Voice' is that it can have troubles with transcribing if the person has a strong accent or in an area with alot of noise, eg. Train station
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