As a mobile reviewer, I frequently switch between phones, making SIM cards a crucial part of my workflow.
Transferring a phone number can be complicated, especially when switching from iPhone to Android.
My experience with T-Mobile has been impacted by the carrier's recent changes.
It's no big deal to pop the SIM card out of one phone and move it over to another as my assignments (or my flights of fancy) dictate.
However, Apple's shift to an eSIM-only model in the US two years ago has altered this process.
Author's summary: T-Mobile's changes affect phone number transfers.