Some observations with the Apple SIM: - If you select AT&T as a carrier, you get this message: "Once activation completes, this Apple SIM can only be used with "AT&T". You will need a new Apple SIM if you change carriers in the future". Very disappointing. So much for switching carriers at will. I have not seen the same message when selecting Sprint or T-Mobile, but I didn't go beyond the initial plan selection screens yet. - T-Mobile has a quite attractive introductory offer: 5GB of data for 5 months for $10.