Google's Project Ara remakes the smart phone by taking it apart

"Project Ara" may not be a household phrase yet, but it could have a profound effect on the smart phone you'll be holding in your hands in a few years.

Part of Google's Advanced Technologies and Products division, Project Ara has an intriguing mission: To build a smart phone with components that can be swapped out, like Legos, allowing its owners to change, add, or improve its capabilities without having to buy a new phone.

Given that brand new smart phones fetch more than $600, the idea is compelling. Smart phone users (iPhones excluded) already routinely swap out batteries to squeeze out more talk time or add more storage via high-capacity memory cards. Imagine being able to make the phone you love faster by swapping in a faster CPU and RAM. How about a larger display with more resolution? Need a new jack to enable your phone to interface with your home's security system? Just snap one in.

It's an idea that seems to go hand-in-hand with another DIY concept: 3D printing, which already allows consumers to create some custom parts. Maybe one day, the parts will be for your phone.

A recent article in The Verge indicates that Google engineers may produce a simple, or "gray" version, of this phone as early as this year. But as the article also points out, the challenges of getting one into the market are considerable.

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Bulk

Devices with interchangeable parts are often more bulky. We see it in smart phones in our Ratings. The phones you can crack open to replace the battery are often a tad thicker than their unibodied counterparts. The challenge is more severe with an Ara phone because components will have to be large enough for consumers to literally grasp—not a concern for engineers who build the sleek phones in our grasp today.

Short battery life

Early Ara-phone experiments have come up short when it comes to battery life. While we don't really know how short, Google engineers say the test results they've been getting have to be at least 25 percent better for the phone's active time to be acceptable to consumers. The phones currently in Consumer Reports labs can typically function for a full day before needing a charge.  

Performance

With electronic devices, performance is a team sport. It's not just about a processor, or a memory chip, or any piece of hardware or software. It's about the way these component work together. So, replacing one component may not yield the desired result. Also, despite efforts to the contrary, there undoubtedly is going to be a "version 2" Ara phone with a unique set of benefits that will leave Ara 1 phone owners envious.

If you build it, will they come?

One of the great promises of an Ara phone is that component makers can compete to offer consumers choices about upgrades while keeping costs low. But what if nobody "goes for it," as we saw with Microsoft's Zune MP3 player and other commercial flops?

If you break it, who will fix it?

Do you think Samsung is going to fix your Ara phone after the Sony-made display fried it—or at least you suspect that was the problem? We already see the hot-potato hassles Android users go through when their phones stop working properly. Carriers blame the phone makers, and the phone makers blame the carriers or the operating system. iPhone owners rarely face such heartaches because they can always turn to the company that made the phone and controls its ecosystem: Apple.

It may take years before consumers will be able to get their hands on an Ara phone. But when or if they arrive, Consumer Reports engineers will be ready to take them apart to see if you should even bother.

—Mike Gikas