While using GIO I move back and forth quite a bit between my laptop and the iOS app. There are two inconsistencies between the two that makes it a bit harder for me when I'm going from one to the other. It would helpful if these were changed to be consistent.
In the topic list, the date/time shown below a topic with more than one message is that of the newest message on the website, and the oldest message on the app.
When opening a topic with more than one message, the default sort has the newest message shown at the top, and the oldest on the app.