Apple's Tuesday announcement that the new iPhone 17 Air will only be available around the world without physical SIM cards marks a new advance for the virtual eSIM technology the firm has relied on in the US for years.

- What is an eSIM? -

Physical SIM cards contain all the information a phone needs to connect to a mobile network using the contract and number of a specific subscriber.

Users have been slotting the fingernail-sized plastic cards into their phones for decades when setting up a new handset, switching providers, or traveling.

eSIMs contain digital data with the same information as physical SIM cards, providing a "secure means for authenticating devices onto networks," the GSMA global standards-setting body says.

Most handsets released in recent years are capable of working

See Full Page