How do I force iOS to check for updates? I've got an iPad2 that's supposedly susceptible to the latest encryption hole in iOS 7.  However, it's not offering me the update automatically.  Where can I go to force it to check for updates?
To check for it manually, go to Settings -> General -> Software Update.

Your device will then check with Apple's servers and let you update if there is newer software available, otherwise it will show you the current version and tell you that you're already up to date.