Hi,
I really like the iOS app. it's very handy for approving blog comments when I'm away from my desk but there's a couple of things that make it difficult to use.
When you are on the Notifications/Comment screen, it often only shows the first few characters of the post title. so its hard to tell what post it relates to, and as far as I can tell, there is no way to click through to see the actual post it relates to. The solution would be to make the "someone commented on your post "XYZ..." part a link that would take you to the post in question.
The second confusing item is the combination tick/cross icon for approving the comments. Does seeing a tick mean it's approved or not? when you touch the tick, it becomes a cross. does that mean its approved or not now? (I know the answers to those questions, I'm just illustrating how they can be confusing). I'm not sure quite how this could be improved but perhaps using a word instead of an icon, much like the web interface for approving comments?