Stockpile lets you buy and sell stocks like most other stock trading apps, but it also allows you to gift single shares of stock or buy fractional shares with a very low cent trade fee. Finishing third, TD Ameritrade stands out for offering two separate apps, Mobile and Mobile Trader, for traditional investors and active traders, respectively. Charles Schwab allows its customers a wide range of assets to trade, including hundreds of commission-free exchange-traded funds. Interested in reading more reviews?