Tools typically cater to placing orders, tracking stock trends, stock screeners, and alerts. Use the Snapstock feature to learn more about the company behind any retail product with a barcode. You can invest in a portion of a share instead with a much lower minimum investment. First is the basic TD Ameritrade Mobile app, which gives you much of the power you have on your desktop stock trading app in a mobile experience for iOS, Android, and Windows phones. Follow along for reviews of the best stock trading apps and may the market forever be in your favor.