What is a GPP unlocked iPhone?

What is a GPP unlocked iPhone?

Added (1). Are these the phones that people buy from a courier in another country and leave with the phone without paying the total amount yet and use a gpp chip to enable the phone to support other couriers?

http://www.tindahannijuan.com/2016/10/08/gpp-and-factory-unlock-iphones/

  • Will an unlocked iphone 4S work for tmobile if it isn't factory unlocked? I want to get an iPhone 4S and my friend has the iPhone 4 unlocked but i'm worried that if i get it non-factory unlocked it won't work. My uncle tried to do it a couple of months ago and apple said that if it was factory unlocked every time the phone shut off or died it would reset. I was just wondering if the same thing would happen if it wasn't factory unlocked? So if I get it unlocked everytime it will shut off it will reset? That is what i'm worried about.
  • Why factory unlocked iphone 4s is showing that the iphone is not activated? I bought factory unlocked iphone 4s on ebay for my sister-in-law who is in europe. And the seller assured that it is factory unlocked and will work perfectly. I have non activated sprint sim card and when i inserted it in to the iphone it showed that "the iphone is not activated.contact the carrier". What does it mean? Does it mean that the phone is not factory unlocked?
  • Unlocked vs factory unlocked iphone? So I'm thinking about getting an iPhone but I wanted to know if I could take an unlocked iPhone to the Verizon store an them set it up for me? I have no clue what the difference between factory unlocked, unlocked, and locked iPhones are
  • If I Buy A Factory Unlocked/GSM Unlocked Iphone 5, Can I Use It With T-mobile? I'm not exactly sure what factory unlocked or GSM unlocked mean, but I just want to know If I can use the phone with T-mobile or if I'd have to switch carriers.