Approximately 63 percent of smartphone users used their handsets to access the Internet last year and 34 percent used their phones as their primary tools for going online, according to Pew Research. From those numbers, it's clear that the way the world connects has changed.

Along with those changes, threats to online security have changed as well. Taken together, the changes have made mobile security more important with each passing day.

The very nature of mobile devices, the mobility, adds an element of vulnerability that isn't a big worry on other platforms. Simply losing a phone or leaving it with the wrong person for a while can now lead to compromise that's as serious as having malicious software mine through the devices.

Commercial offerings are typically a must-have for business professionals who share, transfer and store internal documents on mobile devices, and often corporate IT teams handle the security work.

But for consumers who use smartphones and tablets solely for personal communications and entertainment, free security tools offer enough protection for now -- yet that could all change with a emergence of a new threat.

McAfee Mobile Security

The most rounded of the security tools in this list is the McAfee Mobile Security free app, which shines in anti-theft and anti-spam protection.

Users can blacklist or whitelist text-message sources and phone numbers, even employing keywords and wildcards to do so. 

McAfee Mobile Security's anti-theft features include the ability to remotely wipe, lock, locate and unlock trigger alarms on mobile devices. The aforementioned features can be triggered via text or the web.

While McAfee Mobile Security outshines most mobile security tool options, it falls behind in failing to offer quarantine and on-access scanning -- on-access scans should be initiated routinely and can be triggered by file system changes. An on-access scan is a type of antivirus program which runs in the background and looks at your computer system constantly for viruses and other malicious threats

Sophos Mobile Security

Offering the ability to quarantine suspicious files and to scan file systems on demand, which are deal breakers for some users, Sophos Mobile Security offers a more rounded suite of anti-malware tools than McAfee's product.

All the products listed here scan apps, support cloud-triggered scanning, USSD blocking and have the ability to vet apps for privacy violations.

Sophos shares many of the anti-theft features offered by McAfee, but falls short in failing to offer a web interface and the ability to remotely locate devices. McAfee also has better support.

CheetahMobile Clean

Like Sophos, CheetahMobile Clean offers on-access scanning and quarantining that McAfee lacks. From there, the three tools offer similar anti-malware tools.

CheatahMobile Clean offers a rounded collection of anti-theft tools, though it's missing the ability to track lost or stolen devices in real time. Its anti-spam tools fall short of the others, as it only offers the ability to blacklist or phone numbers.