Q: iPhone 5s Factory Unlocked and Nano Sim

Yes.  You would need a nano sim.  It is what enables you to use a GSM phone.  You would need to make sure the carrier you choose offers nano sims.

linesniper wrote:

 

I'm getting ready to buy a Factory Unlocked iPhone 5s and had a question about Nano SIMS.

 

Just to be clear, there is no such thing as a "factory unlocked" iPhone. iPhones are neither locked not unlocked until they are first activated. At activation time the phone checks Apple's database and either locks the phone if it shows as locked in the database or leaves it unlocked. Note that the ONLY place you can purchase an unlocked iPhone is directly from Apple, either online or at an Apple store. There is no other legitimate source for unlocked iPhones.

No.  There is only 1 sim at a time.  You would need one for the carrier that is providing your cellular service.

It is the same for all iPhones, although the iPhone 4 uses a micro sim.

No. There is only one SIM in the iPhone. It contains the information necessary for your phone to access your carrier's network.

linesniper wrote:

 

Is this exclusive to the 5s or all iphones?

 

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All iPhones.

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ALSO, am I correct in my understanding that I will have two SIMS in my phone (Nano plus my plan's SIM?)

No, only one nano SIM.

No.

Read this:

http://support.apple.com/kb/HT5163