The SIM is an integral part of the GSM standard and provides a huge range of benefits. The point of their existence is to establish the identity of a subscriber independently of a handset, which has a lot of interesting, useful and important side-effects.
A very large proportion of GSM subscribers use dual-sim handsets, to take advantage of the cheapest available tariffs. This is the norm in price-sensitive markets like China, India and Africa.
Many GSM subscribers use several phones with the same SIM. Outdoor enthusiasts switch their SIM between their smartphone and a rugged dumbphone. Some ladies use a smartphone during the week when they use their normal handbag, but switch to a tiny dumbphone for parties.
The SIM makes life very easy for small carriers to connect new subscribers. In London, virtually every shopping centre and high street has someone handing out SIMs for Lyca or Lebara, two Virtual Network Operators offering cheap international calls to mainly immigrant customers. They can connect subscribers on the spot in a matter of seconds.
IMO we should be working in the opposite direction, towards a proliferation of SIM-like devices in other markets. A physical token which securely establishes a pseudonymous identity on a network is quite ingenious and facilitates all sorts of really elegant HCI.
The problem here is that Americans haven't ever experienced a competitive mobile telephony market where all carriers use the same network technology and switching networks is trivial. That's probably why our coverage is terrible and we pay 3-5 times more than people in other countries.
(North) American telco misregulation is a disaster.
To be fair, most of what you're talking about can be achieved without the use of a physical device. The features are useful, the "SIM card" is not.
But your first example isn't like that: the SIM card, in essence, is a form of two-factor authentication. And it's really useful that way. Unfortunately it's a pity that it can only be used by the carriers...
It also expands consumer choice, if only incrementally.
For example, the US carrier T-Mobile has a whole lot of customers with iPhones despite not offering it themselves. That's possible because consumers are able to pick up a used GSM iPhone and stick their SIM card into it.
That isn't really happening for US Cellular, because Verizon and Sprint's (SIMless) handsets can't readily be made to connect to talk to their network.
I've found that the opposite is true when traveling - every new country I go to requires a different (local prepaid) sim card. My iPhone 4S stays the same, but I end up with a new sim card and phone number while I'm in the country, and then end up throwing out the sim card once I leave.
A very large proportion of GSM subscribers use dual-sim handsets, to take advantage of the cheapest available tariffs. This is the norm in price-sensitive markets like China, India and Africa.
Many GSM subscribers use several phones with the same SIM. Outdoor enthusiasts switch their SIM between their smartphone and a rugged dumbphone. Some ladies use a smartphone during the week when they use their normal handbag, but switch to a tiny dumbphone for parties.
The SIM makes life very easy for small carriers to connect new subscribers. In London, virtually every shopping centre and high street has someone handing out SIMs for Lyca or Lebara, two Virtual Network Operators offering cheap international calls to mainly immigrant customers. They can connect subscribers on the spot in a matter of seconds.
IMO we should be working in the opposite direction, towards a proliferation of SIM-like devices in other markets. A physical token which securely establishes a pseudonymous identity on a network is quite ingenious and facilitates all sorts of really elegant HCI.