No Cash, No Checks, No Problem Peer-to-peer payment apps are one of the newest ways to send money. Share | Have A Question About This Topic? Name Email Address Question Thank you! Oops! Related Contents The Power of Compound Interest Learn how to harness the power of compound interest for your investments. Life and Death of a Twenty Dollar Bill How long does a $20 bill last? What Is My Current Cash Flow? Assess whether you are running “in the black” or “in the red” each month.