How to unlock an iPhone

Photo credits: Stockphotosforfree.com 
So you just bought an iPhone or had one sent to you from abroad only to insert you SIM card and BAM! The “SIM card not detected” or “no SIM card detected” error greets you. This could be rather confusing and frustrating to say the least so in this guide, I’ll be breaking down how to unlock the iPhone so you can fix the issue all by yourself.
What does it mean to unlock an iPhone?
Unlocking an iPhone is the removal of SIM restrictions placed on the iPhone by its carrier. The aim of unlocking an iPhone is to be able to use any service provider / SIM card on the iPhone. There are two types of unlocking

• Hardware unlock: Involves manipulating hardware components of the iPhone (not recommended for novices).
• Software unlock Involves the use of software and is much easier than the hardware unlock.

Why are some iPhones locked to a particular SIM card or carrier?
When you purchase an iPhone from a particular carrier as part of a promo or plan, that carrier locks the iPhone to itself so you can’t use any other service provider on that iPhone. Looking at it from a businessman’s perspective, it makes sense (more users = more money); but, from a user’s perspective, it sucks!
What are the things to consider before unlocking an iPhone

• Be sure that the service provider / carrier you’re about to migrate to supports the iPhone’s technology.
• Check your firmware (OS) version and Baseband (Modem) version

How do I check my iPhone’s OS version?
Go to Settings > General > About > Version
What is jailbreaking?
Jailbreaking an iPhone is similar to rooting an Android. To jailbreak an iPhone means to manipulate its firmware to make it run unsigned code and give a user access to files which Apple normally wouldn’t grant access to. One common benefit of jailbreaking an iPhone is the ability to install apps from sources other than Apple store.
Is it legal or illegal to jailbreak an iPhone?
Apple claims that jailbreaking is an infringement of its copyright but I don’t know of any average iPhone user who has been sued for jailbreaking.
What is the difference between jailbreaking and unlocking?
Jailbreaking involves lifting firmware restrictions (file access permissions) while unlocking involves lifting carrier restrictions (SIM / carrier lock)
What are the benefits of jailbreaking an iPhone?
Jailbreaking voids your warranty but some of its benefits are the ability to:

• Install 3rd party applications rejected by Apple for various reasons
• Do video recording (now available on the iPhone 3GS)
• Change the look and feel by installing custom graphics and themes
• Do free tethering
• Get access to cracked App Store apps for free
• Unlock your iPhone

How do I jailbreak an iPhone?
To jailbreak an iPhone, simply follow this guide @ http://www.ay-gist.com/2015/12/how-to-jailbreak-ios-902-on-any-iphone-ipad-using-pangu9-guide.html
How do I unlock an iPhone?
Alright, let’s get down to unlocking your iPhone.

• You need to jailbreak the iPhone (see method above)
• Once you have jailbroken your device, download and install the Ultrasn0w 6.1 package. To do so, launch Cydia and click Manage. Then select Sources > Edit and choose Add this repo: http://repo666.ultrasn0w.com
• Go to Cydia Search and search for official Ultrasn0w Fixer 6.1 then install it.
• Go to Search again and search for Ultrasn0w v1.2.8. Download and install it by adding the repo http://repo666.ultrasn0w.com
• Once the Ultrasn0w package is installed, reboot your iPhone.
• After the device is rebooted, wait for the carrier network signal to show up.
• After the carrier network signal appears, your iPhone will be unlocked with Ultrasn0w Fixer for iOS 6.1. Now, you should be able to switch your carrier SIM.

After unlocking an iPhone, what next, what should i do or not do?
You are strongly advised to avoid updating your iTunes or firmware (OS) version as this could result in your iPhone getting locked again…. back to square one.