Facebook logging into wrong app on iOS

You probably have two applications on your device that have the same Facebook URL scheme in the application Info.plist. You can either:

• Remove the old app, or
• Reinstall the old app but remove the Facebook URL scheme from the Info.plist file beforehand

You may have more than one URL scheme. If so, you should look for the one that looks like fbxxxxxxxxxxx, which is displayed on your app page on http://developers.facebook.com/