https://wccftech.com/motorola-razr-will-be-the-first-esim-only-smartphone/

Motorola Razr will be hitting the market with a number of 'firsts' which include a vertically foldable OLED in a clamshell form factor and eSIM only support. While the former is the most striking and visible feature of the phone, the latter is very significant. Motorola has not built-in a traditional SIM tray, which means that Razr will only work with networks that support eSIM. Razr will be the first eSIM only smartphone in the market.

eSIM is short for embeddable SIM and it is a part of the device. It does not require a physical SIM card to activate a cellular connection and can be switch between networks via a software interface. A physical SIM requires a slot to be created in the hardware, which takes up valuable space. eSIM gets rid of such a requirement, which is why it is already being used in a number of popular smartwatches like Apple Watch. Companies like Apple also take advantage of eSIM as a mechanism to connect to a second network. Apple's dual SIM iPhones sold in most parts of the world don't support two physical SIMs, they support a physical nano-SIM and an eSIM.