You might spend your subway commute playing Candy Crush. The person next to you is tweaking their portfolio.
That act defines mobile trading: using your smartphone to access trading software, allowing you to buy and sell stocks (and any other securities you want) via a mobile network.
Originally, stock trading involved a bunch of bigwigs under a buttonwood tree. Then it consisted of fat guys in funny coats yelling at each other on the floor of the exchange. Now it’s you, on your phone, sitting on the toilet...mobile trading. Progress.