Finding relevant apps and resources can often be quite challenging, especially as there is just so much out there! Also sometimes you hear of something and have to play around with it to find out how it works, and more importantly how it can be useful for the way you teach.
I found an app (by chance as I was randomly flicking through the hundreds of education apps) called Teachers Tech that collates Web 2.0 resources by catagory, and also collates video demonstrations on various well known resources (such as WordPress, Prezi and Wikispaces etc.). The layout of the app is a little jarring on the eyes, but the information it presents is very interesting.
Another useful resource is Edutecher, the website is a fascinating place to search for web resources and they also have an app called Edutecher Backpack. You can link to the forums through this, as well as search the resources. So it is a useful app to have a look at.
Last of all there is App Advice, although this is not a education specific collection of app reviews, it is a very useful place to find out all sorts of things. They review apps of all sorts (and are often brutally honest), there are frequent news stories related to the world of Apple (quite a few that I don't bother looking at). Thier app is very good, you can look up lists of apps and they rated into different categories.
When I first got my iPad I had a good look through their 'apps for teachers' list, and few several excellent apps (some of which I have already reviewed).
They also have a daily list of 'apps gone free', which occasionally has some very useful apps on it.
Although you do have to pay for the app. The amount of money I have saved in finding free apps more than makes up for it.