Most of the current technology buzz that's not dedicated to Apple's never ending pre-release Watch hype centers on the latest crop of 2015 smartphones, mostly HTC and Samsung releasing their latest iterations of their respective, long-running, flagship phones.

But the most interesting smartphone of 2015 will almost certainly end up being a prototype device from Google, possibly filled with quirky, stylish, geeky, and well-marketed components from a mobile manufacturer that most people haven't heard of... yet.

Project Ara: Don't Call it a Smartphone

That "smartphone," if you want to use the shorthand (neither the singular nor plural form of that word entirely applies), is Project Ara.

For those who've never heard of it, Project Ara is the name of a mobile technology concept announced in 2013 and now headed into its final phase of development before its first market trial in Puerto Rico later this year.

Not exactly "a" smartphone, Project Ara is the first try at a mass-produced mobile device with a modular design. In layman's terms, think of a flat Lego board with pieces you can snap on and off that provide any and all of the smartphone functions you're familiar with.

Like that Lego baseplate, Ara's core is a metal "endoskeleton" that provides slots for swappable components, called modules: Camera, storage, battery, and speaker modules (and so on), as well as a large screen module in front, all puzzle-piece together to make a highly customizable -- an most importantly, easily upgradeable -- smartphone.

The idea is like the Moto X's Motomaker customization engine taken to the next level. Don't care about anything but selfies? Don't bother buying a rear-camera module and use that slot for a bigger battery instead. Phone feeling sluggish and out-of-date? Don't replace the whole thing; just buy an upgraded processor module.

New 'Spiral 2' Developments

The latest public update has Project Ara at "Spiral 2" and headed towards "Spiral 3" ("Spiral" is just Google's quirky term for the phases of the Ara prototype). The current Spiral 2 Ara was most recently unveiled earlier this month at the Mobile World Congress.

So far, Google has the baseplate "Endo" in good shape, with electro-permanent magnets to hold the modules in place and, according to The Verge's sneak peak, it's also developing an app that allows for ejecting specific modules while the phone is running.

This could change the way stored media is transferred from mobile to other devices, if for example, a USB-pluggable storage module could be easily ejected and returned to the phone.

Google is reportedly first working on hot-swappable batteries, though. The company says its current design allows users to replace a dying battery module with some fresh juice while Ara continues running -- if they can complete the swap in about 30 seconds or less. The target goal is reportedly to expand the battery swap time to a minute or two.

At this phase, the Endo can hold eight modules of differing sizes on the back, with large space for a screen module (so far, Ara has been seen with a working 720p display) and another space at the top for a receiver (speaker) module on the front. Ara currently works with 3G networks (another module), but the next phase will take on 4G LTE connectivity.

Yezz's Role

Yezz is the little-known mobile firm based in Miami -- with a company image seemingly tailored specifically for young, hip, tech-savvy Latinos (one of whom is the company's founder, Luis Sosa) -- that has taken Google's call for OEMs to make modules for Project Ara and run with it.

The company is developing not only a standard set of core Ara modules -- 3G/SIM, 5-megapixel rear camera, wifi/bluetooth, USB port for charging, a headphone jack, a "standard" battery, a 1.5GHz quad-core system-on-a-chip with 1GB RAM and 8GB storage, and a rear speaker module, reported by Tom's Hardware -- Yezz has also let its collective creativity run wild with concepts for future designs.

In fact, it has a 100-page book full of sketches for possible modules.

Still just concepts, some possibilities include more capable core modules, like one single module that could provide 128GB storage, 2GB RAM, and a much faster SoC processor. Others are more fanciful ideas, from a separate notification bar for the top-front Endo slot, to the tech press's current favorite example: a module on the back for a breath strip dispenser. One assumes there's no app for that.

Yezz also designs the back-plates for the modules to appeal to the market Ara is launching in: Its 4G concept component features the Puerto Rican flag, while another concept for a graphics module has the image of Darth Vader printed on the back.

A Grand Experiment, Launching Later

None of the cleverness of Google's current designs, nor the hip creative marketing of Yezz, guarantees that Project Ara will ever become anything more than an interesting idea that a few enthusiasts in Puerto Rico got their hands on before the whole idea was scrapped.

But at the moment, Ara certainly seems primed to capture the imagination of smartphone consumers -- especially young ones who want a custom experience and are weary of the constant upgrade cycle draining their bank accounts at least every two years.

We, Google, Yezz, and other OEMs like Toshiba that are cautiously dabbling in the modular concept, will find out this year though, as the Puerto Rico launch is set for "sometime" in late 2015 -- but only after Google finishes "Spiral 3," while Yezz presumably works like crazy to make its Ara dreams a reality in time for launch.