open keychain Access select login under keychains and certificates under category remove all your developer certificates close
open xcode click on sheme on top left by device selection edit sheme .. on left select Run , on top select info uncheck the debug executable close
build and run your app
after I got my app running successfully, the Simulate Location does not work anymore...(Debug->Simulate Location), and select location options do not show anymore on the debug area in the main screen bottom. Can someone confirm does it still work on your Xcode? Thanks.