I tap on the icon for the app, the splash screen appears, and then it promptly crashes back to the home screen without a trace.
I've updated to the latest version of the app and the latest version of iOS but that hasn't helped.
I've tried turning the phone off and back on again and that hasn't helped either.
I'd like to try uninstalling and re-installing the app, but it's not clear how to do that from the phone itself. I've tried to do so from iTunes on my PC, but it warns me that "This app will not be deleted from any iOS device that synchronizes with your iTunes library."
I'm at a loss. I guess what I'm eventually going to have to do is just upgrade to the latest iPhone since it doesn't look like this old version is going to receive any more support.