[atonse]

GitHub is popular because it's popular. A lot of it is network effects. As far as I can remember, they were the first user-friendly git web host. (Key being user-friendly).

GitHub has also been really great at giving back to the community (in ways that even GitLab has benefited I'm sure).

But I doubt the source of their popularity is the integration, although their robust APIs have made the ecosystem around them flourish.

[briandear]

The integrations are specifically why I use Github. When I had been on Bitbucket projects a few years ago, I remember how deficient they were with integrations. It was painful using Bitbucket for that specific reason.

[modzu]

well they also did some cool stuff like electron and github desktop

[BugsJustFindMe]

It's true that they also make widgets, but the proportion of people who use GitHub because of their desktop client has to be vanishingly tiny. GitHub became popular originally because of pull requests. It stays popular because of network effects that counterbalance its deficiencies (terrible search, weak bug management, short analytics window, etc).