Well, known iOS researcher Jake James is the Developer of RootlessJB ( iOS 12 to iOS 12.2). Brandon Plank released Rootless Jailbreak for iOS 12.4 version. Rootless Jailbreak is the only tool not installing Cydia or Sileo ( Third Party app managers ) after completing the jailbreak process.
After completing the process Rootless Jailbreak gives access to var sub directory and then you can install jailbreak tweaks by using Rootless installer or Filza.
iOS 12.2 / iOS 12.1.4 / iOS 12.1.3 / iOS 12.1.2 / iOS 12.1.1 / iOS 12.1 / iOS 12.0.1 / iOS 12
Rootless jailbreak can be installed as two methods. The first method is by Online ( Without computer ). The second method is the side loading ( Cydia Impactor ) method.
Rootless Jailbreak is the only tool not installing Cydia or Sileo third party app managers, but it gives access to var sub directory.
There are a few different methods to install Cydia tweaks after using RootlessJB.
The RootlessInstaller method is the easiest one to install jailbreak tweaks.
RootlessJB is a semi-untethered jailbreak tool. So you have to re-jailbreak after every reboot and respring. Open the RootlessJB app and Tap Jailbreak again.
Checkra1n semi-untethered jailbreak support iOS 12.3 to the latest version running iPhone 5s to iPhone x Device. Checkra1n still does not support an online solution. So it would help if you had a Mac or Linux Machine ( Windows version yet to be released ) to use the Checkra1n jailbreak tool.
Pwn20wnd is the Developer of the Unc0ver tool. Currently, Unc0ver jailbreak tool supports iOS 11 to iOS 12.4 as a semi-untethered jailbreak solution. According to Pwn20wnd, Unc0ver upcoming version of Unc0ver will be a jailbreak solution for iOS 13 to iOS 13.3 including A12 and A13 Devices.
iOS 12 - 12.2 & 12.4 versions fully compatible for Chimera jailbreak tool. Sileo is the third party application manager for Chimera jailbreak tool.