Merginal (GitHub: idanarye / vim-merginal) by Idan Arye is a Git branch merge tool. It has an interactive UI for viewing branches, checking out branches, merging branches, and solving merge conflicts.
The branch list supports some keyboard commands, including
R to refresh the buffer list, and
M to merge the branch under the cursor into the currently checked out branch.
I like tools that help me step through merge conflicts because it's usually something that I struggle with when working in feature branches. I often use vimdiff as a mergetool, but even then I find it hard to visualise changes in certain file types -- XML regularly breaks my brain.