Some free jailbreak downloads for the iPhone are the Evasi0n jailbreaking tool, PP Jailbreak, Pangu, and RedSn0w. Jailbreak tools are released free for download by their developers for anyone who owns an Apple device.
Evasi0n is developed and maintained by a group called Evad3rs. The latest version jailbreaks Apple devices running iOS 8, iOS 7, iOS 6.1.3, 6.1.2 and earlier versions of iOS 6. It can run on Windows, Mac OS X and Linux systems.
A team based out of China created the Pangu tool. The first version was used to jailbreak iOS 7.1.1-running devices, and it was only available for Windows users and only in the Chinese language. The latest version is in English, is Mac-supported and can jailbreak devices running, iOS 7.1 to iOS 7.1.1, iOS 8 to iOS 8.1., and iOS 9 to iOS 9.0.2.
Developed by the PP team based out of China, PP Jailbreak was used to jailbreak iOS 8 to iOS 8.2.1 and worked on Mac OS X. The same team was the first to develop a jailbreak for iOS 8.1.3 to 8.4 that could support Mac.
RedSn0w is the most widely known and used free iOS jailbreaking tool, and it is regularly updated, compared to other tools. It evolved from Quickpwn, an earlier jailbreaking tool, and works on both Windows and Mac systems. It has a host of other features, such as fixing Recovery Mode loops, and it jailbreaks devices running iOS 3 up to iOS 6.1 Beta 3.