According to billionaire venture capitalist and Facebook board member Peter Thiel, it is.
In a recent interview with The New York Times, Maureen Dowd questioned Thiel in a series called "Confirm or Deny." When he was asked to confirm or deny that the age of Apple is over, Thiel confirmed, saying, "We know what a smartphone looks like and does.
It's not the fault of Tim Cook, but it's not an area where there will be any more innovation." - Source