https://www.cnet.com/news/qualcomms-new-5g-multimode-chip-means-sleeker-phones-better-battery-life/

"This converges 30 years of cellular and wireless innovation and R&D from Qualcomm all into this one chip," Nitin Dhiman, Qualcomm staff manager of product marketing, said in an interview. The company made the announcement ahead of the Mobile World Congress confab in Barcelona. 

The X55's predecessor, the X50, was unveiled two years ago but is only now making its way into mobile devices. The chip only connects to 5G networks, which means handset makers also have to include a second modem for 4G, 3G and 2G in their devices. The X55 changes that, letting companies buy one chip for the various networks.