Update: Reports say that the update is now working again, so go ahead and find those iPhones.
A new update for Apple’s Find My iPhone app seems to have been pushed out a little early: It changes the icon to a flatter design, which is more in keeping with iOS 7’s aesthetics. Unfortunately, it also locks out users on iOS 6 who don’t have a registered developer account or iOS 7 installed and configured on one of their devices with their iCloud account.
In other words, the vast majority of users should not update Find My iPhone just yet, unless you don’t want to be able to actually … find your iPhones, MacBooks, iPads or whatever else you’ve registered with Apple’s MobileMe service. If you’re a registered developer with iOS 7 installed on at least one device, you should be fine, even if you’re updating on iOS 6, but otherwise wait to avoid that update and Apple will likely issue a fix soon.
We’ll keep an eye on this and let you know when it is safe to update the app, since that’s kind of a big part of Apple’s cloud services on its mobile devices.