With RIM firmly dethroned, the battle of supremacy in the U.S. smartphone market comes down to Google's Android OS and Apple's iOS.

Data from Nielsen suggests that Android is firmly in lead with 39 percent of the market share while the  iOS trails with 28 percent.

However, the iPhone remains the most popular phone because the Android OS runs on many diverse devices. 

The most popular Android OS device manufacturer is HTC, which only has 15 percent of the total smartphone market share from Android phones.  Motorola trailed with 11 percent and Samsung followed with 8 percent.

Therefore, all HTC Android phones have less than 15 percent market share, all Motorola Android phones less than 11 percent, and all Samsung Android phones less than 8 percent.

In the smartphone industry, though, the size that currently counts is the OS market share because of the importance of apps.

So far, Apple has the lead arguably because of its first-mover advantage.  However, if the Android continues to pull away in market share, its sheer size will tip the scale in its favor.

Apps was the big trend in smartphones that RIM missed.  It's also a major reason that RIM was dethroned.  For the Google and Apple battle, capturing the next big smartphone trend is key.

Steve Jobs and his prescient genius have a stellar track record of generating the next big thing.  If Apple succeeds again in this regard, Google will need to play catch up and perhaps lose its lead to Apple.

However, the advantage of Google is the diversity afforded by its open system.  If the next big trend spawns from the general technology world, the Android platform has a better chance of capturing it. 

The argument of Apple iOS vs Google Android goes beyond the battle of two OS; it's a debate between open and closed systems, optionality versus elegance, and platform versus product.

In the 1990s and early 2000s, the rise of the Internet seemed to anointed openness and platform as the future.

However, Apple's string of wildly successfully and highly-controlled products has challenged this assumption.