Checkra1n was the first jailbreak tool for iOS 13 based on the checkm8 exploit. A few months after the checkm8 exploit was first released, a new open-source jailbreak tool named Fugu has been released.
Made by LinusHenze, Fugu is an open-source jailbreak tool for iOS 13 that’s based on the checkm8 exploit. The tool is still under development and in its current form, it is meant only to be used by developers. Fugu currently supports the 2017 iPad Pro running iOS 13 – iOS 13.3.1. The iPhone 7 should also be supported, but it has not been tested by the developer.
Say Hello to Sileo!
(iPad Pro 2017, iPadOS 13.1.3, custom Jailbreak, not checkra1n) pic.twitter.com/dHhS8CDPVl
— Linus Henze (@LinusHenze) October 28, 2019
The developer notes that while it is possible to install Sileo or Cydia, most of the jailbreak tweaks will not work. He also warns that while the root filesystem is mounted as r/w, if one reboots their device in non-jailbroken mode, the root filesystem will be reset to stock.
This jailbreak is currently in development and only meant to be used by developers. While it is possible to install Sileo (or Cydia), most tweaks (and probably other stuff) won’t work. Additionally, although the root filesystem is mounted read/write, rebooting into non-jailbroken mode will reset the root filesystem back to stock!
Like checkra1n, Fugu also requires you to connect the iPad to your Mac to start the jailbreak process. Right now, LinusHenze has only released a Mac app for the Fugu jailbreak tool and it is unclear if he plans on releasing a Windows version of the tool or not.
For now, your best bet to jailbreak your iPhone or iPad running iOS 13 is checkra1n. The Fugu jailbreak tool is clearly meant for developers and advanced users and not for the average joe. The latter does support iOS 13.3.1 which checkra1n lacks support for, but it is also more complicated to use and supports only the iPad Pro.
You can download Fugu from here.