Re: how can i sign out gmail from samsung z1
Welcome to Android Central! On an Android device, you never really sign out of your Gmail, since it's part of the Google account that the whole phone is logged into. You'd have actually have to remove the Google account from the phone, which is not feasible. If you want to access multiple Gmail accounts, just add the second account, and you should be able to access both in the Gmail app. Just swipe in from the left and select the account you want to use.
If you're asking about signing out due to privacy concerns, then the answer is to make sure you have a good screen lock.