I recently needed to add an appointment to iCal that was a couple of years from now on my iPhone. I began tapping on the forward arrow but as that was getting tiring I thought I'd try keeping my finger pressed down on the arrow. I found that it quickly skips ahead by months, and it only took me a second to get to my desired date.
[kirkmc adds: This seems more useful to view a future date. To set an appointment, just tap and hold a date when in Month view, and you can then set the date from the Add Event dialog. Just tap on the Starts or Ends dates and set the date you want there. Or, if you are using an iPhone 4S, just use Siri.]
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