It's only commercial software if you use it for commercial purposes. They have a pretty liberal non-commercial license as well. SmartGit is free to use for any of these purposes:

* to actively work on open-source projects,

* for learning or teaching on a public academic institution,

* in the spare time to manage projects where you don't get financial compensation for (hobby usage),

* by public charitable organizations primarily targeting philanthropy, health research, education or social well-being.

(Wording is from their license, English is not their first language.)

https://www.syntevo.com/documents/smartgit-license.html

For open source alternatives, a few people I've worked with like SourceTree. I don't think it has the integrated reflog though. I'd be curious about other recommendations too.