If you need to share bills with friends for expenses like rent or groceries there are a number of great services like Splitwise that help you split bills. Now you won't forget that IOU you have coming. If your friend has credit they can pay you immediately with a credit card using Square. It allows anyone with a bank account and smartphone or iPad to accept credit cards and charges a fixed percentage fee for every payment you receive using it. Accepting credit cards is no longer limited to businesses.