When turning on iPhone 5c, get gray screen with white dots
iPhone 5c. When I turned power on this morning, I get only a gray screen with white circles (dots). No normal sign-on screen or request for passcode. Phone is fully charged. If I dial the phone's number I get a normal ring and prompt for voicemail, but no way to answer. Any thoughts? Hugh A.
iPhone 5c, Mac OS X (10.4.11)