If you don't want Google to store your chat history and the Google chat history of the person you are chatting with, you can take the chat off the record and this is how you do that.
If you were wondering where in Gmail can you actually see all the contacts you have stored with the help of your Android phone or any other way, this is how you get to see them.
A really great Gmail functionallity that enables you to send emails from your other email addresses using your main Gmail account. Let's find out how to add other addresses to your account.