Logging into Facebook on iPhone?

I have FB app on my iPhone when I open the app to sign in it signs me straight in instead of me putting in my email and password I dunno what I've done but how do I change it. It says I'm signed in on ios6.

When in fb app, click the side bar and scroll down and click log out. Nxt time u launch app it will ask for password.

Or you can go in settings in the iphone and edit fb.

You can either logout from the Facebook Application itself or follow bellow option.
Login to facebook from your web browser
Go to Account Settings >> Security >> Active Sessions
End all active sessions shown there.
After this is done you can go to Facebook Application from your iPhone.

Thats Because you have it Set to Remember your information if you want to do this log out than uncheck the remember info and next time you log in using the app it won't remember your Facebook info

Be Sure to Log Out Everytime you are Done With Facebook on your Iphone