Three new products of Apple are in the market similar to iPhone X (we can say update version of iPhone X) name as iPhone XR, iPhone XS, and iPhone XS-Max. For ease, we mention here almost all the things that make these three products different from iPhone X (In the form of Comparison).
Processor- iPhone X is equipped with A11 Bionic chip with Neural Engine where iPhone XR, XS, and XS Max are equipped A12 Bionic chip with next-generation Neural Engine. The A12 Bionic delivers incredible performance. It uses real-time machine learning to transform the way of photos, gaming, augmented reality and more. A12 is Up to 15% faster and consume 50% lower power than A11 Bionic. The Neural Engine is incredibly fast, able to perform 5 trillion operations per second.
Water resistant- iPhone X is capable to resists water Maximum 1 metre of depth up to 30 minutes where iPhone XS and XS Max can resist water 2 metres of depth up to 30 minutes. iPhone XR has the same water resistant feature as iPhone X.
Primary camera- iPhone X comes with only Portrait mode image capturing feature and Auto HDR where iPhone XR, XS, and XS Max come with Portrait mode with advanced bokeh and Depth Control and Smart HDR (Smart HDR brings more highlight and shadow detail to your photos).
Secondary camera- Extended dynamic range (for video at 30 fps), Portrait mode with advanced bokeh and Depth Control, Smart HDR and Cinematic video stabilization are the additional features as compared to iPhone X.
Dual SIM- Simultaneously, we can use two SIM in iPhone XR or iPhone Xs or iPhone Xs Max, a nano-SIM, and an eSIM. An e-SIM is a digital SIM that allows activating a cellular plan from the service provider without having to use a physical nano-SIM and this is one of the most awaited features of Apple iPhone.
Audio Playback- iPhone XR, XS, and XS Max come with wider stereo playback that improves stereo spread and an elusive sweet spot in tracks where iPhone X comes with only stereo playback feature.
Cellular and Wireless- iPhone XS and iPhone XS Max support Gigabit-class LTE where iPhone XR and iPhone X support 4G LTE Advanced.   How to Setup wifi Hotspot in iPhones and iOS
Video Recording- Advanced video recording that provides an Extended dynamic range for video up to 30 fps and Stereo recording but all these features are absent in iPhone X.