As promised, Pwn20wnd has released the 40th beta version of the Unc0ver v3.0.0 jailbreak for the public which now supports for all pre-A12(X) devices running iOS 12.0-12.1.2.
Unc0ver beta 40 supports the iPhone 5s, iPhone 6, iPhone 6 Plus, iPod touch 6G, iPad mini 2, iPad mini 3, iPad mini 4, and iPad Air.
Also, Pwn20wnd announces on Twitter that it added bundles Cydia and an updated version of a working Cydia Substrate.
With this updated Unc0ver jailbreak tool, you can easily jailbreak your device.
Note: Before attempting the jailbreak, it is highly recommended to turn on the Airplane Mode.