) A chip that is equivalent in function to a Mini or Micro SIM card used to identify the telephone number in a cellphone. With the traditional SIM card, changing phone numbers or carriers requires replacing the card in the device's SIM tray. However, an embedded SIM is built in and programmed remotely by the carrier. Google's Pixel 2 phones and the Apple Watch 3 with Cellular were some of the first devices to employ eSIMs.
eSIMs are also used in wireless machine-to-machine devices that have permanent identities. See SIM card