Yes I have logged in from my phone to bitstamp and I had there my google authenticator installed.
Yes I had my email account with the password saved on the same phone
Yes it was connected to a 3g data plan
This means that the criminal(s) could steal all your money if they indeed have compromised your phone and I am guessing this is the case here. :-/
This is a rather sad and expensive life lesson for you. I hope you and others learn from it.
Sad and expensive indeed ...
I hope you will recover soon.
Try to keep tracking their wallet address with your btc. One day they must spend it. Maybe they will do a small mistake and you will be able to track them. But perhaps this would be difficult.