Apple Inc. took the wraps off the iPhone 4's sequel earlier this month. The new phone, called the iPhone 4S, has seen remarkable pre-order numbers. Pre-orders for the iPhone 4S started on Oct. 7 and has since registered 1 million units on the first day, surpassing the previous single-day record of 600,000 for the iPhone 4.

The product was made available in the U.S., Canada, Australia, United Kingdom, France, Germany and Japan on Oct. 14. Apple said it has sold 4 million units of the iPhone 4S during the opening weekend.

Meanwhile, Apple is set to release its fourth quarter earnings on Tuesday, after the market closes. Analysts are expecting Apple to issue more details of iPhone 4S unit sales at the earnings conference call.

As expected, the iPhone 4S featured some important upgrades that were rumored to be a part of the imaginary iPhone 5, like the 1GHz dual-core ARM Cortex-A9 processor, PowerVR SGX543MP2 GPU, an Apple A5 chipset and an 8 megapixel LED-flash camera with 1080p HD video recording. It also has a 3.5-inch TFT Retina multi-touch display and is loaded with Apple's latest Operating System - iOS 5.

In addition, the iPhone 4S also comes with alternating antennae for better call reception, CDMA and GSM support, a personal assistant called Siri, iCloud and Bluetooth 4.0 wireless technology. However, prominent specs like edge-to-edge design, a larger display, 4G LTE and Near Field Communication (NFC) technology were missing.

We expect a more material 4G iPhone revision in mid-to late-2012 together with the expected launch of the iPad3 in early-to mid-2012, said Scott Sutherland, an analyst at Wedbush Securities.

Solid Launch

On Friday, we did checks with over 15 Apple, AT&T, Verizon and Sprint stores, with follow-up checks on Sunday at several of the same stores, said Sutherland.

He said the Sprint 16GB version of the iPhone 4S was sold out at both Apple and Sprint locations by early Friday, although stores still had the iPhone 4 in stock. Sprint representatives indicated this was partially due to receiving modest numbers of the new unit.

He further said that Verizon stores saw moderate demand, with lines on Friday of only 20 people. AT&T stores had longer lines, some with over 50 people at the start of the day. By Sunday, several AT&T stores were out of the 16GB iPhone 4S, with some out of the 32GB units as well.

Apple stores, as usual, had very long lines but also the most stock. He noted that the stores he visited on Sunday continued to have a steady flow of iPhone customers.

With the largest global launch of a new iPhone, on over 100 carriers, and positive comments out of China Unicom and China Mobile (not even a formal iPhone partner), he believes the iPhone 4S will be the most successful iPhone launch (by far) to date.

Impact on RIM and Nokia

Sutherland believes the iPhone 4S puts additional distance between Apple and Research In Motion Ltd. (RIM), just when the BlackBerry maker has come out with several new smartphones.

With the iCloud and momentum gained by connecting to other devices in the Apple ecosystem, he believes RIM is falling farther behind.

With recent network outages, he also believes that RIM has shown some serious cracks in its core stickiness. As for Nokia Corporation, he believes the new Windows Mango phones cannot come soon enough.

While his expectations are modest for the first two, he believes more interesting devices will be introduced next year. He also expects Nokia to highlight major feature phone enhancements later this month.