The email invitation shows a big "12," for Sept. 12, casting a shadow in the shape of a "5."
Various unconfirmed reports have pointed to Sept. 12 as being the day Apple Inc. shows off the new phone, which is expected to go on sale a week or two later.
The next iPhone is expected to have a taller screen and the ability to access the latest wireless data networks in the U.S. Analysts expect it to set sales records.
Other unconfirmed reports say Apple will reveal a smaller version of the iPad, taking on competitors like Amazon.com Inc.'s Kindle Fire, which have nibbled on the edges of the iPad's dominance in the tablet category.
On Wednesday, Nokia and Motorola are holding events of their own in New York, apparently to reveal their latest products ahead of the iPhone launch.
Apple shares rose $5.18 to $676.42 in afternoon trading. The shares are close to their all-time high of $680.87, hit a week ago.