I have made this Android app as a tool for keeping information about who's turn it is to pay for the meal next time :)
Application allows creation of groups of people who are added from Contacts on person's phone. When the people from group go for a meal, owner of the phone adds the information about bill (person who payed, date and restaurant name) into the app, which is then send via SWMS to all the members of group for their safekeeping.
Application was created in AppInventor.