The difference between "offline" and "signed off" is the amount of time you will be away from the app. If you are stepping away from your phone but expect to be coming back to it shortly, you can switch to "offline" so you do not continue to receive trips. If you are signing out for the day and do not expect to be taking any more trips, you can "sign off".
If you plan on signing off for the day, please be sure to go "offline" first, and then sign out of the app. This way you do not continue to receive trips while you are trying to sign out. It also allows data from your trips to be sent to our systems.