Given the huge rise that Apple has had over the years it's an easy call to say that it has to come off the boil sooner or later. This chart shown in the log scale shows a series higher lows following a series of cycles. The depths the price reverts to lines up with previous all time highs (blue lines) with a regression to the purple trend line dictating the direction of the overall trend. This is going to take some time to play out, but it seems reasonable.