First came discount brokerages in the 1970s, which made it cheaper to buy stocks. Then trading became commission-free, and smartphone apps made it possible to buy and sell stocks from anywhere. In the latest step toward democratizing investing, online brokerages led by Robinhood Markets Inc. in the U.S. are seeking to make buying and selling shares not just cheap but seamless and even fun. That’s drawn a new class of U.S. retail traders into the market. It’s also raised worries about what happens when the “gamification” of investing obscures the connection between price and value, fueling the phenomenon known as ...
