IPhone factory unlocking is just differ from other branded smart phones such as smart phone giant Samsung, HTC,Sony Experia, LG and etc. these type of smart phone are being unlocked by nck code . Once you inserted the unofficial sim cards that will ask code to continue, that's very easy to unlock but IPhone should be unlocked by the server using a third party man so that's why is the IPhone's unlocking cost may be high than usual smart phones.
Most of low cost IPhone unlocking services on the internet are scam, third party Google advertisements, sites with attractive animation images are classified as scams. Most of them aren't show their indentity in the internet. Some of them are good. In my personal experience , if you are new in the terms of unlocking in the internet , you'll be easily get scammed.
Nowadays you'll be heard about Activation lock is introduced in ios 7, this is most important in IPhones. You can secure your IPhone from thieves once turned on "findmyiphone" in icould setting with your Apple ID and password, your IPhone could be tracked in the map.
If you planned to bought used iphones , should off "findmyiphone" otherwise you'll be struck on activation screen with prompt apple ID and password of former used person . If he is also forgot that password. You can remove it with limited time service , this removal service is only working with clean imei not barred or blacklisted or insurance claimed and reported as stolen. Also you can remove previous apple id without password if you access home screen with small fees. So that "findmyiphone" should off before order any IPhone unlock services.
Find my IPhone must turned off.
Still in contract then you should continous pay the bill.
No software available in the internet for factory unlocking service , if yes that's surely scam.
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