Question for developers – Tab - The simple bill splitter Review

How do you undo a mistake? I will be going to lunch with a group that is older and not tech savvy. I did a practice run of this app, made a “mistake” (choosing the “wrong” entree) and couldn’t figure out how to correct it. Great app. I just want to be sure I know how to work it!
Review by Molnarnj on Tab - The simple bill splitter.