Pay Your Share is one of those handy apps that you may want to have permanently installed. It's a simple and straightforward app, fitted in an brilliant and step by step interface, that allows to sum all the expenses (usually regarding a dinner, but it can be anything) and divide them among those who took part.
How it works:
1) In the first screen you have to add the people involved and the amount of money that he or she spent (prior to the event)
2) In the second screen you have to add the items of dinner. These items will then be divided.
3) In the third screen you have to tick or untick expenses according to who ate or did what.
4) In the last screen you will see an expenses sumary that each other must pay.
Once all the Math is done, you can save or share your results. Oh, sure this isn't the first app to calculate group expenses, but have for sure there's been a huge effort to synthesize it all and make not the mistakes other did.
Now you can change screens with top buttons or slide.