Samsung's (NASDAQOTH:SSNLF) latest smartwatch is also a smartphone: The upcoming Galaxy Gear S is equipped with a 3G modem. What that means is that unlike just about every other smartwatch currently on the market, Samsung's Gear S does not need to be tethered to a nearby handset -- it can make or receive messages and calls on its own.

If the Gear S proves popular, it could send shockwaves through the mobile space -- unlike Samsung's Galaxy handsets, the Gear S does not run Google's (NASDAQ:GOOG) (NASDAQ:GOOGL) Android operating system.

Samsung's Tizen phone is here
Samsung has been developing its Tizen operating system for years. Executives at the Korean tech giant have, at various times, claimed that the company was on the verge of releasing a Tizen-powered handset, only to later delay the phone indefinitely.

The Gear S isn't a smartphone in the traditional sense (it is, after all, a watch) but it is powered by Tizen, and because it can function without an accompanying handset, it's arguably Samsung's first Tizen-powered smartphone. Samsung's other Gear watches (with the lone exception of the Gear Live) also run Tizen, but need to be paired with an Android-powered, Samsung-made handset in order to make or receive calls.

Replacing rather than augmenting
The Gear S, then, is unique in that it's the first smartwatch that could replace -- rather than simply augment -- a smartphone. Samsung's prior smart watches have not sold particularly well -- perhaps because they do not offer much beyond what Samsung's Galaxy handsets can already do.

The Gear S could be an exception -- a spare smartphone to use in special situations (while jogging, for example) or a replacement for a traditional handset entirely. The later seems unlikely, given that the Gear S has a relatively minuscule screen and disappointing specs, but might be possible over time, especially if Samsung continues to rapidly improve on the concept with future models.

A chance for Tizen to shine
Samsung's rival in the Android handset market, Huawei, is skeptical of Tizen. In a recent interview with The Wall Street Journal, Richard Yu, the head of Huawei's consumer business group, said quite bluntly that Tizen had "no chance to be successful."

As a smartphone operating system, that may be the case. But could Tizen succeed in a different form factor?

Google's take on smartwatches -- Android Wear -- does not offer anything in the way of independence. Like Samsung's prior smartwatches, Android Wear-powered devices are very much extensions of a user's smartphone -- they make it easier to use a smartphone, but they cannot stand on their own. Samsung's Gear S, then, is likely to face virtually no competition. If other rival tech firms wish to offer similar devices, they may be forced to adopt Tizen or otherwise design competing smartwatch operating systems of their own.

If Samsung's Gear S succeeds in attracting millions of users, it could help Samsung establish the Tizen ecosystem it seems to crave. As it stands, Tizen has virtually no support in the way of app development, largely because it has no users. In contrast, there are more than 1.3 million apps on the Google Play app store, and more than 1 billion Android devices in use.

This is why Yu is so skeptical of Tizen. He told The Journal that "It's easy to design a new OS, but the problem is building an ecosystem around it."

Adopting a new form factor may be one way to solve that that problem. As a radical new device, Samsung's Gear S could convince consumers to trade a lack of apps for unprecedented mobility.

An unproven concept
Of course, there's no guarantee that consumers will be swayed. Although both Samsung and Google have bet on them aggressively, smartwatches in general remain an unproven concept.

Nevertheless, Samsung's Gear S is shaping up to be one of the most revolutionary gadgets released this year. The odds against it may be high, but if it is successful, it could help Tizen emerge as a legitimate mobile operating system and redefine the concept of a smartphone entirely.