Depending on how you count it that could be a version originally released in 2018 i.e. the version they are aiming to support is 3.28 which you should be able to easily update to from 3.0 (which was released in 2018) since it's a minor update with no breaking changes
So I would say that it's currently "technically" a paid-for app. It seems like they are doing something like Sublime with a "nagware" approach. I have been using it since it was free and haven't actually needed to pay for it yet. Having said that I will probably pay soon anyway because it is such a valuable tool for me.
As for using Fork vs other apps, I used to use SourceTree before Fork. Fork is my favorite right now because it is less opinionated and really just exposes the Git functionality directly. For example SourceTree made it impossible to force-push because they didn't believe you ever should.
There is another class of app for Git that is like a subset or overlay, like the way GitHub desktop uses "sync" instead of real Git terms. I remember Tower also felt like it was trying to make me see things the way it wanted me to and not the way Git worked but I can't remember the details.
I did kinda address this in the post. While it's true that you can do everything that Fork can do in the command line (and supplement that with a branch visualiser), everyone but the people most comfortable with Git will avoid even attempting the techniques outlined in the post. I would estimate that this is probably less than 10% of devs (possibly far far less)
Using something like Fork actually makes the whole process of interacting with Git much more enjoyable, and therefore will encourage people to use more intermediate or expert aspects of Git to their full advantage.
Ha ha ha! I wasn't expecting to be quoted in this article :) but I can confirm that someone did actually tell me that about not wanting to recommend Ember
Well the fact that both of the founders are Irish really helped the matter ;) I think you can get one if you move to Ireland but you have to be really committed to the url you want!