If I received a refurbished iphone,can I require apple for a brand new one?

Sorry, yes, I should have specified that in the USA, Apple's unconditional return period (ie. for full refund) for iPhones is 30 days, but for iPads and iPod Touchs it is 14 days. Things may vary around the globe, and if you buy from an Apple authorized reseller, and not direct form Apple, they may have their own store return policy as an option as well.

As I say, technically you cannot exchange an item during that unconditional period - what you technically have to do is return the one you have for a full refund, then buy a new one. However, in an Apple Store, if you say that is what you intend to do, what they actually do is just take yours and hand you a new one (instead of actually goint through the process of refunding your first one and making you go through the full purchase checkout for a new one).

Apple does not repair any iOS devices and never has. So, they also have never instituted any repair technician training programs nor have they ever offered parts for sale or order, hence there is no officially authorized 3rd party repair for iOS devices either. What they do is take yours, swap if for one that has been fully refurbished by the actual manufacturer in China in their factory, and then Apple sends your old one back to the manufacturer for refurbishment (if it is suitable for that, otherwise it gets recycled). This is the same deal with most sealed solid state mobile devices including ereaders from B&N and Amazon and other tablet makers - its just far more cost efficient to let the actual manufacturers do all the work on such tightly integrated and basically sealed devices.

It's always possible, but it's unlikely. Only if Apple is out of stock on refurbished service units for a given model and don't expect more soon would they substitute new stock. It's not something that is at the customer's option.

Regards.

No, there's no differences. The serial number is different because each iPhone is unique.

Refurbished iPhone is not better than brand new one. It's the same as or as good as the brand new one.

Apple does indeed replace your phone with a "remanufactured" device. I took my phone into the Apple store due to faulty wifi hardware, when he brought out I asked if it was refurbished and he said no it was "remanufactured" I had no say as to whether I recieved new or "remanufactured" device. It would have been okay had I purchased a refurbished device but I didnt and the damage to the phone was through no fault of my own. Little dissapointed in Apple...