Dear Lifehacker, A friend of mine recently acquired a new phone and had to get a new SIM in the right size. That made me wonder: why do we still use SIM cards? American CDMA phones are SIM-less, so are there any specific reasons why SIM cards are still needed here? Thanks, Had My Fill Of SIMs
Picture: Simon Yeo
It is true that many US phones that use the CDMA network don't utilise a SIM — the phone connectivity is programmed directly into the phone. This would be theoretically possible with other network types — your phone doesn't care whether it reads network details from a card or the phone's own memory. However, it hasn't generally been the approach in the Australian market, and we think that's a good thing.
While it's annoying if you switch from one phone to another and suddenly discover you need a micro- or nano-SIM, being able to swap your SIM means it's much easier to acquire an additional SIM if you travel overseas, or to switch from one provider to another if you decide that prepaid is a better deal. If you have a phone which doesn't have a SIM slot at all (as some US CDMA models do), then that simply isn't possible. You're stuck with the network who supplied the phone, or at best switching to another network which also offers SIM-free access. Why limit your choice in that way?
The lesson here is two-fold: buying a second-hand phone from a US seller is risky, and being able to swap SIM cards is useful. On modern smartphones, you'll usually be able to do this without requiring an unlock code or other details from your provider — but it does pay to check before you head overseas, especially if you have an older phone that was purchased on contract.
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