iFixit observed that the battery inside the iPhone 4S is rated at 5.3W-h (Watt-hour) capacity, slightly more than the 5.25W-h of the batteries used in both the AT&T and Verizon iPhone 4 models of 2010 and early 2011.

Also inside the iPhone 4S is a multi-network baseband processor -- the silicon that lets the smartphone make and take calls -- said iFixit and iSuppli.

"The iPhone 4S merges the HSPA and CDMA radio capabilities found separately in the two previous iPhone 4 models into a single product that can address global wireless networks, making it a world phone," said iSuppli. "No other handset OEM produces a single device for multiple operators and for multiple geographies on this scale."

During the unveiling of the iPhone 4S last week, Apple also touted the new handset as a "world phone" because the same model can be used on both GSM- and CDMA-based networks.

Lam of iSuppli had last spring based on the appearance of a Qualcomm baseband processor in the Verizon iPhone 4.