iPhone XS and XS Max are Apple's newest flagship phones, and the successors to Apple's 2017 iPhone X. They have the new A12 Bionic chip, improved cameras and faster FaceID, and come in a beautiful Gold Stainless Steel finish in addition to the Silver & Space Gray options. They are available in the same 5.8" Super Retina display as with the X, and the bigger 6.5" Super Retina. They are available in 64GB, 256GB, and 512GB configurations.
Apple added Dual SIM technology to the 2018 iPhone's, with one physical SIM, and one eSIM. (eSIM feature not currently supported by Sprint, but is said to be coming later). These phones also feature IP68 water-resistance (iPhone X was IP67) which gives you protection in water for up to 30 minutes in up to 2m of water.