See: Mobile Banking. See: Mobile Commerce. See: Mobile Marketing.
Pretty much every financial institution has a mobile payment app now. Super-easy to click from your account at Wells or PayPal or Venmo or B of A or whoever, and zap someone that $22 you borrowed for lunch (it's actually on the back of the ACH system, usually). It was a nice lunch.
Society is getting more and more mobile, in the sense that few people hand-write checks on paper any more. Computers are way easier to process, store, and manage financial data.
Download an app if you haven't, and get smart on the future. You'll be glad you did. Maybe.