I have a lock on my phone for the soul reason that if it is lost or stolen then the thief or the person who finds it can not use it. Yes, there are ways to unlock phones but by the time they crack it I will have reported the phone lost and I signal will be sent to the phone which blocks it and no good for anyone.
We both have access to each others Facebook and I often log on my fiancée account and chat with her friends and add pictures. Lol
She often logs on mine, I do not know if she posts and chats to my friends but to me, it is only cyberspace and not the real world, if I log on one day and find out I have come out and confessed I am gay or I have just married Hillary Clinton I would just laugh. The real world and being true and honest with my woman is all that really matters.
One last think, she does not have access to my bank account, come on, get real.