TALK TO TEXT, Words, Vocabulary and punctuation are all features of your keyboard.
Keyboards can be changed to fit your work needs or even your personality. To Talk to Text, use the microphone on the keyboard.
Here are some top Android choices http://tinyurl.com/m6dp49j
You can also search the web and Play Store for other popular keyboards.
AUDIO TEXT MESSAGES
You can send an audio message via text using the mic on the app located next to or near the ‘typing space’. In a conversation: Hold down the mic. Speak your message. Release the mic when you are finished speaking.