This is just a minor suggestion, but I think the "up arrow" button that appears in the action bar when selecting a comment on the Android app should be changed to "thumbs up".
After all, the button is used to give 'score' to a good (or amusing) comment. (Or, using the terminology of a certain social media, to "like" the comment.)
Yes, the website uses an up arrow to do this. But I don't think it is necessary to fully emulate this piece of interface in the context of a mobile app.