I couldn't find a way to approve / comment on / request changes for PRs. It'd be nice to have that possibility in the app.
@sschuberth thanks for reporting, review prs isn't correctly implemented yet there is an open issue for it in #375 #429 , next version you'll be able to reply to reviews, interact to them via emojies and maybe after that there will a way to review the PRs.
Thanks for the info. But actually, I believe none of the linked issues is a strict duplicate of this issue:
All of these are different from being able to do what is possible from this dialog in the web UI:

@sschuberth Oops, please forgive my misunderstanding. I thought they are somehow related. I'll try and do that, but can't promise you anytime soon, but its in my list.
this should have been closed few days ago :D . I hope I didn't close another issue instead.
Thanks @k0shk0sh. Mind explaining where the feature to add review summary comments and approve reviews is hidden? I was unable to find it in the UI so far.
@sschuberth its in the nightly builds.
Will be in the next public release too.