Voice Typing Is A Great Feature in Google Docs- Here Is How to Use It | Android and iPad apps for language teachers | Scoop.it
From www.educatorstechnology.com - December 16, 2015 6:33 AM
There are several speech to text extensions that allow you to type with your voice in a Google document  (e.g Speech Recognition, Voice Recognition). However, Google Docs itself has a powerful integrated functionality called Voice Typing which is overlooked by many users. For now, Voice typing in Google Docs is only available on computers and only in Chrome browsers.

Via Gumersindo Fernández