Venmo is an app that lets you pay your friends back electronically. Its convenience makes it extremely popular on college campuses. It definitely comes in handy when splitting a restaurant bill, gas money, etc. However, its growing popularity has led to its use as a form of payment for even more official transactions, such as ticket purchases and dues payments. Plus, if a friend you invited to join the app gets Venmo, both of you get a nice little bonus of $2. Avoiding the hassle of paying people with exact change and earning a little cash on the side makes Venmo a highly desirable app.