If you've ever called your carrier's customer service to activate a prepaid SIM card or troubleshoot a malfunctioning Android ...

The only exception would be emergency calls to 911, which you can place even without a SIM card. ICCID (Integrated Circuit Card Identification Number): This is a unique 18-22 digit code that is ...

If you purchased your device from T-Mobile, the SIM card is probably installed. If not, you must provide your phone's IMEI number. The customer service rep may also ask for the ICCID number on ...