iPhone 5s comes in three storage sizes: 16GB, 32GB and 64GB. The term “GB” stands for gigabytes. The more gigabytes you have, the more content you can store on your iPhone — apps, games, photos, HD videos, music, films and more. For example, if you have a large music or photo library or you frequently download HD films, it’s a good idea to consider an iPhone with a larger storage capacity. If you have a relatively small music or photo library or rarely make or buy films, an iPhone with a smaller capacity may be better for you. Of course, over time you will accumulate many things on your iPhone, so you’ll want to think about how your storage needs may evolve.
About the unlocked iPhone
Unlocked iPhone isn't tied to one network, so you have the freedom to choose any supported GSM network worldwide. Buy unlocked iPhone at the Apple Online Store, then find a SIM-only plan for iPhone. Or contact your existing carrier to continue with your current plan.
About Pay as you go.
If you don’t want a service plan, you can add a Pay as you go starter pack from one of the available carriers at the Apple Online Store. With Pay as you go, your iPhone arrives ready to use with a compatible SIM and no credit check is needed. You just pay online for what you use and you can change networks at any time. Pay as you go is a good option if you prefer to use a local network when travelling abroad.
What kind of SIM card do I need?
Whether you are starting a new service contract, using your existing one or choosing Pay as you go, you need a compatible SIM. For iPhone 5c and iPhone 5s you need a nano-SIM card. For iPhone 4s you need a micro-SIM card. Contact your carrier for details.






