I saw this lament and my first thought was, she does not live in Kenya, but in backward New York. A truly mobile wallet — one that would let you easily pay for restaurant meals, subway rides or beers at a bar with a quick wave of your cellphone — has long been described as imminent. But it remains elusive. Some innovations have begun to bridge the gap, but most have been a disappointment or have not yet worked well enough for mainstream adoption. In 2012, Square, which makes a credit card reader that can be plugged into an iPhone or iPad, worked on a credit-cardless system that let people pay for goods without ever pulling out their wallets or phones.