On Sept. 12, Apple (NASDAQ: AAPL) simultaneously discontinued last year's flagship smartphone, the iPhone X, and launched the iPhone XR, XS, and XS Max. The XS directly replaced the iPhone X, while the XS Max offers a significantly larger screen for $100 more. Although not too much has leaked out about Apple's 2019 iPhone lineup, I think it's safe to assume the company will introduce successors to all three of this year's models.