Apple Ready For September Event

It's expected Apple will unveil an iPhone 6S at the event.

The event is scheduled to start at 10 a.m. PT and will be held at the Bill Graham Civic Auditorium.

Apple is remaining tight-lipped about the agenda for the event and in a characteristically coy invitation teased, "Hey Siri, give us a hint."

For those who take the invitation literally, Apple is even having a little fun with Siri. Ask the virtual personal assistant "Siri give me a hint," and she will fire back: "Why don't you check a rumors blog? That's what I do."

Among the biggest updates expected for the possible new iPhone release are an even sharper camera, faster processor and force touch technology, allowing users to press parts of the screen the same way they would a button, according to reports.

ABC News' Neal Karlinsky contributed to this report.

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