There is a problem with the app under iOS 5, which causes it to crash and so we have pulled the app for the time being. An update has been submitted to Apple but we are waiting for them to accept it. It normally takes between 1 and 2 weeks, so we’re hoping it should be sometime this week. The app will be back on the app store as soon as Apple accepts the update.
We’re really sorry for any inconvenience caused.
We will also be launching a new version of our mobile website in the next few days, which makes it very similar to the iPhone app.