Xiaolian Jailbreak Team is from China, they hope jailbreaking could be an interesting area to explore. So after a conference, they started make public jailbreak for iOS 11.0-11.2.6. Xiaolian Jailbreak is the first public iOS 11.2+ jailbreak for all arm64 devices which includes Cydia and substrate. 

Here is the jailbreak demo:

Site: http://xiaolian.fun/

Notes

1. Please make sure to always check shasum.

2. After you jailbreak using Xiaolian, you will get a new default repo in Cydia. This is where system updates can be downloaded, through Cydia.
3. If you remove the repo through ssh, you cannot expect us to support your device if you are not up to date.
4. This version requires a developer account due to the way Ian beer's exploit works.

And Xiaolian Jailbreak Team claimed that they will release public jailbreak for iOS 11.3.1 soon. 

3u Team has not tested it yet. If you are interested in using this jailbreak, please be extremely careful and take your own risks. 

Update:  GeoSn0w recommends against using this jailbreak. 

Do not use this Jailbreak. It’s a knock-off of the older Electra Jailbreak with multi_path and it’s most likely not even working. Since this has a pretty hefty file system footprint, it may cause problems with the official Electra so stay out. https://t.co/9QnlUySJOS

— GeoSn0w (@FCE365) June 25, 2018