* Official invites for the unveiling of Apple’s next iPhone on October 4 went out yesterday. Piper Jaffray’s Gene Munster believes the company will only release one new model — not an additional low-end version, as some have been speculating — along with advanced voice recognition features. (Fortune)

* Amazon (AMZN) is holding a company event in New York City that kicks off at 7 AM PST/10 PM EST today. If the rumors are to be believed, it may be the much-rumored Amazon Kindle Fire, a 7-inch reading-focused tablet with a color display. Keep an eye out for our coverage later this morning for details.

* Sprint apparently plans to launch its own 4G Long Term Evolution (LTE)-based network early next year to better compete with the likes of Verizon. (CNET)

* Within one to two years, Facebook mobile chief Erick Tseng believes half the social network’s users will access it via mobile devices. (TechCrunch)

* Why Facebook works for all, but Twitter only works for some. (The New York Times)

Don’t miss the latest tech news. Sign up now to get Today in Tech emailed to you each and every morning.