While hardware vendors are always quick to tout specs, the smartphone wars are being won and lost on the software battlefield. BlackBerry's newest operating system, BlackBerry 10, suffers from its late start -- unlike Apple's iOS and Google's Android, BlackBerry doesn't yet have an extensive catalog of must-have apps (a problem that also bedevils Microsoft).

Despite this, BlackBerry has brought some novel features to its newest mobile OS. BlackBerry 10 is built around your eight most recently used apps and a universal inbox dubbed "Hub." There are no navigation buttons on this OS -- everything is controlled by directional swipes -- so you can speed your way into and out of various apps more easily (at least in theory). There's a new, virtual keyboard on board as well, which reviewers felt was well-executed. A new web browser, based on technology from Torch Mobile, is also present and reportedly delivers a speedy browsing experience.

Overall, though, reviewers had a mixed take on the BlackBerry 10 OS. While they praised its keyboard, browser and rich interface, the lack of apps was a major sticking point. Like the Z10 phone in which it is debuting, reviewers were convinced that BlackBerry fans would be pleased with the new OS, but avid iPhone or Android users won't find anything worth jumping ship over.