How to jail break an iPhone?

Also, does it then ruin all the games? Or can you turn it off on certain games

Use evasi0n. Go search for it on google there are jailbreak versions available for different iOS versions.It'll crash at times though

Jailbreaking an iPhone does not affect any en-built apps or downloaded games you have on your device. Secondly, jailbreaking an iPhone requires the jailbreak to be compatible with the iOS version your iPhone is running.
Currently, iOS 6.1.2 is the latest version that can be jailbroken, using evasion jailbreak tool. You can find more information here: http://ifanzblog.blogspot.in/p/jailbreak_10.html
Once you jailbreak your iPhone, you can easily customise it - tweaks, visual treatment, etc. Jailbreaking is safe and easy to do. It is still advisable to back up your iPhone before performing the jailbreak.

Depends on which iPhone you have & what version of iOS it is running.

No it will not "ruin all the games".

A jailbreak is not a selective thing & again doesn't affect current running apps.

  • Why won't my iphone properly jail break? After downloading the evasi0n jailbreak I plug in my iPhone 5 version 6.1.2 and the jail break all work until it asks for me to unlock the device and click on the jail real icon, but my problem is that there's no jail break icon at all in my phone. Is it my phone? My computer? Or why dose the icon not transfer to my iPhone, need help please As soon as possible
  • Undo Jail Break on iPhone 4s, do I need to use Tiny Umbrella? I'm using 5.1.1 and did a jail break a week ago but now I want to wipe it out. Can I just restore using iTunes or do I need to use a special program?
  • Should I jail break my iPhone 4? So I have a white iPhone 4 I got a couple weeks ago all my friends have iPhones and most of them have all did it. How do I jail break my phone and is it safe for my phone And what exactly is it?
  • Should I jail break my iPhone? - 1 I've had my iPhone 4 for about 4 months. Some of my friends had their iPhone jail broken but most of them took it off because it was running down their battery. I jail broke my iPod a few years ago but took it off cause I kinda got tired of it. A lot of people are scared to jail break their phone because they think it will damage the software. So do you guys think I should or just leave it as it is?