Keep track of individual bills amongst your friends, family, etc. when at a function or even at a restaurant. Its kept in a neat and easily understandable format to quickly add or subtract item prices with minimal time loss.
Its quick and easy to see the total amount spent by individuals and as a grand total for the evening. Adding a person is no hassle and no waist of time thus maximising your mingling time.
No more adding, subtracting, ... and trying to work out who has to pay for what and how much.