A recent evaluation by AV-Test.org revealed that many free Android security products are barely effective and some don't seem to offer any protection at all. That's certainly a contrast with the PC arena, where many free antivirus products, avast! Free Antivirus 7 (free, direct) among them, perform very well indeed.

In the previous update, avast! added automatic sandboxing, a feature previously found only in avast!'s commercial products. Version 7 adds several more new features including the avast! market page. From this page you can upgrade to the company's full security suite or purchase avast!'s backup and password management solutions. avast! Rescue Disc ($10/once direct, 3.5 stars) is available in the market, as well as a free credit alert service.

Install and Upsell
You definitely won't have to dig into the avast! market to obtain avast!'s commercial products. During the installation and configuration process there are several opportunities to try or buy the Pro antivirus or suite. One window offers "base protection" versus "full protection," with the latter selected by default. Another offers the Pro antivirus at half-price. The welcome window includes an upgrade button, and after registration you'll get an offer for a 20-day free trial of the full suite.

On top of all this, the program's main window includes a time-limited discount offer to purchase the full suite at a discount. Well, you can't blame them for trying. Giving away protection earns a company loyalty and good feeling, but somebody has to pay the bills.

By default, the avast! installer also installs Google Chrome and makes it your default browser. Bundling fees from Google also help fund avast!'s protection giveaway.

Full Scan and Boot-Time Scan
I had no trouble installing avast! on my twelve malware-infested test systems. The setup routine reported a crash on one system, but it recovered and managed to complete the installation without further incident.

The product offers several different scan types; for testing I chose the full system scan. I also turned on the option to scan for PUPs (potentially unwanted programs), which was disabled by default.

In every case, avast! asked to run a boot-time scan, either before or after the full scan. When the boot scan came first, I ran a full scan afterward just to be sure. On my standard clean test system the full scan alone took 21 minutes, well below the current average of 30 minutes. However, running a boot scan added over 20 minutes more.

If you set up a boot scan and walk away, it can take a lot longer than 20 minutes. As soon as the scanner finds a threat it halts, awaiting your choice of action. You can delete, quarantine, repair, or ignore either the threat or all found threats. If you don't choose an option that applies to all threats the scanner will stop and wait for your response for every threat it finds. I choose "move all to chest" (quarantine) in every case. Even after that, if the scan finds a threat locate in the Windows folder you'll have respond to another confirmation prompt.

Boot-time scanning is smart, as it lets the antivirus do its work with no possibility of a rootkit or other devious threat interfering.You'll probably want to configure the boot scan settings to automatically move all found threats to the chest, thereby avoiding any possible hangup.

Effective Malware Cleanup
Avast! scored 6.8 points overall for malware cleanup, which is quite good. Norton AntiVirus 2012 ($39.99 direct, 4.5 stars) took the top score for standalone antivirus in this test, 7.1 points. With 6.9 points, Webroot SecureAnywhere Antivirus ($39.95 direct, 4.5 stars) has the second-highest score among standalone antivirus tools.

Some of the malware samples are rootkits, threats that interfere with Windows to hide their traces. Like many of its competitors, avast! detected all of the rootkit samples. It did leave behind some executable rootkit components, but its rootkit-specific score of 7.6 points has been bettered only by the 8.7 points earned by Comodo Cleaning Essentials (free, 4.5 stars) and 8.9 points by Norton.

I also break out a separate score for removal of scareware, also known as fake antivirus. Avast! joins a crowd of others with 9.5 points for scareware removal. That's good, but Norton and Malwarebytes' Anti-Malware Free 1.51 (free, 4 stars) aced this test with a perfect 10. To learn how I derive these scores, please see How We Test Malware Removal.

avast! Free Antivirus 7 malware removal chart

Less Effective Malware Blocking
In my malware blocking test avast! scored 8.1 points, which is precisely average for the current crop of products. Webroot aced this test with a perfect 10; Comodo Antivirus 2012 (free, 3 stars) came in second with 9.1 points.

Looking specifically at blocking rootkit threats, avast! scored 8.1 points. It detected all the rootkits, but one of them managed to plant executable files on the system and another actually launched its rootkit technology. On the plus side, a full scan did remove the offending rootkit. Webroot, Comodo, and Norton blocked rootkits perfectly, thereby achieving the maximum score of 10 points for rootkit blocking. As for blocking installation of scareware, avast! scored a perfect 10 points, as did almost half of all current products.

For an explanation of how I test malware blocking and come up with these scores, see How We Test Malware Blocking.

avast! Free Antivirus 7 malware blocking chart

Eight "shield" modules provide avast!'s real-time protection against malware; a new page in the user interface offers an overview of shield activity. The web shield was particularly effective at preventing access to known malware-hosting sites. When I tried to re-download my malware collection it blocked most of the still-extant URLs and killed off one threat immediately upon download. With 89 percent of downloads blocked avast! beat all recent standalone antivirus products.

In theory, the web shield should also block access to phishing sites, but I didn't see that at all. I ran my usual antiphishing test long enough to accumulate 25 verified and very new fraudulent sites. Norton blocked 88 percent; avast! didn't block a single one. Given that my antiphishing test is quite time-intensive, I didn't continue.

Good Lab Results
Avast!'s free antivirus gets good marks from the independent testing labs. West Coast Labs and ICSA Labs certify its virus detection in static tests, and it received VB100 certification from Virus Bulletin in nine of the last ten tests. In on-demand testing by AV-Comparatives.org avast! scored ADVANCED+, the highest rating. It scored ADVANCED in the retrospective test, which attempts to simulate zero-day protection by scanning with old signature files.

AV-Comparatives also runs a whole-product dynamic test; avast!'s rating in this test was STANDARD, the lowest passing grade (but still good). AV-Test.org's antivirus certification tests award products up to 6 points for protection, repair, and usability, with a total of 11 points required in order to pass. Avast! took 14 points in the latest test under Windows XP and 12 in the Windows 7 test.

To understand the difference between good lab results and great ones, consider Bitdefender. It, too, passed nine of the last ten VB100 tests. It also has certification from ICSA Labs and West Coast Labs for virus detection, but both labs also certify it for virus cleanup. In all of the AV-Comparatives tests it scored ADVANCED+, and it received 16 points from AV-Test. To learn more about the independent labs, please read the article How We Interpret Antivirus Lab Tests.

avast! Free Antivirus 7 lab tests chart.

Automatic Sandboxing
The full avast! security suite lets users run any program using the product's sandbox technology. A program running in the sandbox can't make permanent changes to the system, which means you can run suspect programs without worry. With avast!'s free antivirus you can't arbitrarily choose to run a program in the sandbox, but if avast! itself determines that a program is suspicious it will automatically sandbox it.

Of course, other program components will handle known malware. Autosandbox only kicks in when an unknown program seems suspicious. New in this edition, you can fine-tune the way avast! decides whether to autosandbox a program. For example, if you're a developer or someone who uses many uncommon programs, you might set it so it doesn't sandbox a file merely due to low prevalence.

In my testing, the only program that triggered this feature was an analysis tool that I wrote myself. Naturally such a program has very low prevalence—nobody has a copy outside my office. Avast! analyzed it and found no sign of malicious activity, but still recommended setting it to always run in the sandbox. Toward the end of my testing, autosandboxing stopped triggering on this tool; apparently my repeated use tilted the prevalence scales enough that avast! no longer considers the program suspicious.

Web Reputation
Many free antivirus products install a browser toolbar for access to security-related features. AVG Anti-Virus Free 2012 (free, 4 stars), current Editors' Choice for free antivirus, goes even farther, with non-security buttons for such things as current weather, Facebook login, and Windows calculator. Avast! takes a more restrained approach, adding just a single button that reflects the current site's Web reputation.

Reputation scores are derived by tallying user votes; click the button to vote on the current site. In addition to rating the site on a five-step scale from bad to good, you can tag it with any of five good and five bad content types. The Web reputation button displays a red or green icon for sites with an overall bad or good reputation; it also reflects a low, medium, or high number of votes. Web reputation icons also appear alongside search result links, so you can steer away from bad sites.

Relying on user votes to define reputation can have its pitfalls, as a determined group can force a specific reputation rating. For example, the FBI's homepage has a bad rating, based on many votes, yet it almost certainly isn't a security threat.

Bonus Features
Comparing the current product with version 6, several new features stand out. I've already mentioned the avast! market page and enhanced configuration options for the autosandbox. The new reputation services feature lets avast! query the company's online file reputation database to make intelligent decisions, and streaming updates speed the process of keeping definitions up to date.

Remote assistance is built right in, so you can get help from other avast! users. On clicking the button to allow remote control you get an eight-character code that you hand off to the helper. On entering that code, the helper immediately gains remote access to diagnose and fix whatever problem you're having. Of course tech support can make use of this feature when needed.

Many Good Choices
There's no question that Norton AntiVirus 2012 and Webroot SecureAnywhere Antivirus, our overall Editors' Choice products for antivirus, are more effective than the current free products. Picking an Editors' Choice specifically for free antivirus is getting tougher. In my blocking and removal tests, Avira Free Antivirus 2012 (free, 4 stars) scores a bit higher than AVG Anti-Virus Free 2012, the current Editors' Choice for free antivirus. However, Avira's rootkit-fighting powers are limited and it flagged one PCMag utility as malware. Avast! beat AVG by 0.3 points in my malware removal test, but scored 0.3 points lower in my blocking test.

Malware removal is important when the product is new, but malware blocking provides ongoing protection. That being the case, AVG remains Editors' Choice. But really, it's a close race. You may want to try avast!, AVG, and Avira and see which one suits you best.

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