I recently purchased a new htc inspire device. This is my first experience with android. I created an account to log into the market place. The prob im having , how does one log out of the market place? when i click on the icon it takes me straight in no password etc. i can then click on an app to buy and there is a stored credit card wide open to use. No password to authorize use or anything.I can see my son going in there an buying everything. I know im just not doing something right. Can someone explain the process?