This is a great way to learn about stock trading without any risk. 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. Part Of. Interested in reading more reviews? The world of mobile trading continues to evolve rapidly. Robinhood launched its mobile app before its website, making this a best stock trading app in its own right. TD Ameritrade Mobile, Mobile Trader The extra cost of trading with TD Ameritrade is worth every cent — the brokerage delivers fantastic platforms, research, mobile apps, education, and customer service.