Bank technology How Amex's Serve Stacks Up Against Competitors Published May 24, 2012 2:07 PM | Updated February 10, 2020 10:47 AM 1:49 Facebook Twitter LinkedIn Email It's a crowded mobile wallet market, with Google, PayPal, Isis and others strenuously pushing their products. Dan Schulman, group president of enterprise growth, shares what he believes are the strengths of American Express’s Serve digital wallet.