I tried a few Git clients over the years and am proficient with the CLI.

My impression is that Fork captures how git actually works better than some of the other GUI tools and it has a lot of handy features that make certain tasks a pleasure instead of a chore (common rebasing things, add/deleting/changing local/remote branches, splitting up changes in single files into multiple commits - this is maybe be an antipattern but I do it frequently enough).

Also, it's very cheap. I hope they make enough money with it to continue development.