An embedded SIM — a programmable SIM built into the iPhone's hardware instead of a physical plastic card. eSIM lets you switch carriers without swapping SIMs, useful for travel. Every Kosher iPhone supports dual eSIM (US carrier + Israeli carrier, for example) so seminary students can keep US numbers while using local data.
Related terms
This term is connected to the broader supervised iPhone ecosystem. See the [full glossary](/glossary/) or return to [how it works](/how-it-works) for context.