Telephony IDs

Android devices with SIM cards and eSIMs use the following IDs in the telephony APIs, including TelephonyManager and SubscriptionManager:

  • Subscription ID: unique ID for a mobile subscription.
  • Slot index or slot ID: unique index referring to a logical SIM slot. Slot IDs start at 0 and go up depending on the number of supported active slots on a device. For example, a dual-SIM device typically has slot 0 and slot 1. If a device has multiple physical slots but only supports one active slot, it will have only the slot ID 0.
  • Card ID: unique ID used to identify a UiccCard.