See all the reviews of an App Store app
One of the quirks of Apple's App Store is that every time a new version of an app is uploaded, the previous reviews for that app are hidden. This can leave you looking at an app listing that says "No Ratings" when in fact a whole load of people have already rated and reviewed the app.
This guide to shows you how to reveal all the reviews for an app in the App Store.
First, look up an app on the App Store and select the "Reviews" tab.
If the app has been recently updated and nobody has added a review since the update, you will see something like this:
This is because the App Store is only showing you the reviews for the current version of the app (i.e. the recent update). To see all the reviews, you have to select the "All Versions" tab.
Hey presto! All the reviews for that app now appear.
I'm not sure why Apple is intent on hiding all these previous reviews, but I certainly like to reveal them whenever I'm considering buying an app.