To get Avast's full security and privacy offerings, you'll have to also install Avast Anti-Theft and Avast Mobile Backup & Restore. You can find both apps in the Google Play app store; the main Avast app can walk you through installation as well. The process is straightforward, but it does make for a much lengthier setup than we found with the other apps we've tested.
The app will ask you to set up a PIN of 4 to 6 digits, which can unlock Avast or the entire phone, as well give you the ability to send commands to the app via SMS.
The home screen of Avast Mobile Security & Antivirus is a simple list of features: Virus Scanner, Anti-Theft, Backup, Application Locking, Privacy Advisor, Application Management, SMS and Call Filter, and Firewall.
By pressing the menu button on our Samsung Galaxy S4, we could check for updates, change PINs and adjust other settings, such as exporting the app's activity log.
MORE: Mobile Security Guide: Everything You Need to Know
Some Android phones lack a physical menu button, so Avast also has an onscreen icon in the upper left-hand corner. This brings up a Settings menu, as well as Avast's Web Shield, App Shield and Message Shield features. We didn't like that the Web Shield, an important feature of most mobile security apps, was tucked away here instead of listed on the home screen.
All in all, however, Avast's interface is well organized and delivers a ton of information in an intuitive and manageable way.
Detection and performance
As you'd expect, Avast's app scans for mobile malware using Virus Scanner. You can check Scan Apps, Scan Storage or both, and tap Scan Now to do a full scan. Automatic Scan schedules daily or weekly scans.
The app's most recent build, Avast Mobile Security & Antivirus 3.0, was 98.7 percent accurate in German lab AV-Test's malware-detection test, finding almost all the 2,191 pieces of malware involved in the test. That's better than AV-Test's industry average of 96 percent. But rival security apps from Norton, Kaspersky and McAfee had perfect malware-detection scores, and Lookout Mobile Security scored 99.4 percent.
We put Avast to the test ourselves, downloading the well-known EICAR test virus through our phone's Chrome browser. Avast didn't alert us when we tried to download the file, but once we did, Avast's storage scan picked up the test virus right away and flagged it as a problem.
When we uninstalled Avast, downloaded EICAR and then reinstalled Avast, it took two scans for the app to notice the file and flag it as malware.
To test Avast's impact on a device's performance, we ran a malware scan while running the Geekbench 3 benchmark. Our Samsung Galaxy S4 notched a score of 2,275 before we installed Avast, hitting a higher 2,345 afterward.
With the antivirus scan running, the phone's score dropped to 1,719. That's a performance hit, or delta, of 626 points. Lookout's mobile security app saw only a 130-point hit, but Avast's showing was better than Norton's delta of 656, Kaspersky's 774 and McAfee's 1,064-point delta.
Anti-theft and data protection
In an unusual setup for a security app, Avast Mobile Security & Antivirus' anti-theft and mobile-backup features are separate apps and must be installed separately. After Avast Anti-Theft and Avast Mobile Backup & Restore are set up, both switch to "stealth mode" and are accessible only from the main Avast app.
You can also tap Anti-Theft or Backup from Avast Mobile Security's home screen, and the program will walk you through the installation of the auxiliary apps. Advanced Installation Mode lets users install Anti-Theft as a rooted application — a separate process for technically skilled Android users — to gain additional features.
Once you install the Anti-Theft app, you'll be asked to register a mobile phone number (a different number from that of the device). You can then activate Avast's anti-theft features from the registered number simply by texting your Avast PIN and a command to the device. Those SMS messages won't be visible from the device's default messaging app.
MORE: Best PC Anti-Virus Software 2014
Avast has all the anti-theft features typical of a mobile security app: GPS locating, remote data wipe, remote alarm and remote lock. Avast provides a few more locking options than the competition: You can lock the device's settings menu or lock its program manager access — so a thief can't install any new apps. And you can lock the entire device.
The app can surreptitiously take photos, but you'll have to activate that feature in the advanced-settings menu of Avast's anti-theft app. From the Avast website, you can send a command to immediately take a picture using either of the device's cameras, or set the phone to take a picture after a certain number of failed unlock attempts. The app will also take a photo using the front-facing camera if it detects a face within a minute of the device's screen being turned on.
You can also set the phone to automatically take a photo if someone tries and fails to unlock the phone. Photos are accessible under the Commands tab in the Web portal.
A unique feature called Geofencing tells you if the device leaves a designated area. When you arrive at a location you'll be staying at for a while, activate Geofencing from the app's Anti-Theft menu; if the device moves a given distance away before Geofencing is disabled, the device will be marked as "lost."
Most other security apps we tested listed their anti-theft features within the app. We liked that Avast did not, because there's usually no reason to track down a phone from the phone itself. A Web portal or another device is the only logical way to access a device's anti-theft features; by not listing those, Avast streamlined its own app.
Avast's Backup feature resembles its Anti-Theft feature in that you first have to install the Avast Mobile Backup & Restore app. The first time you access it, you'll have to agree to another EULA and privacy policy. Then you can choose to give the app permission to access your Google Drive account.
MORE: 8 Best Android Backup Apps
Avast will store your backed-up contacts, call logs, SMS messages, images, audio files, videos and apps on Avast's own cloud-storage service (accessible from the Web portal), on Google Drive or on both. The app lets you opt to back up data only over Wi-Fi (avoiding mobile-data charges) and also set a file-upload size limit. To back up apps, your phone has to be rooted, but this means apps will retain any data or progress you've made, such as scores in a mobile game.
Among the other mobile-security apps we reviewed, only McAfee offered a backup feature comparable to Avast's, although McAfee's can't back up installed apps as Avast's can. Kaspersky Internet Security for Android doesn't contain any backup feature at all.
Avast Mobile Security & Antivirus' other data-protection features include Application Locking, which is available from the main menu. It displays a list of apps installed on your device; check the box next to an app, and all users will need to enter the Avast PIN to open that app.
We also like the Privacy Advisor feature, which shows what kind of information each app accesses, and also detects which apps run what kinds of ads. Avast scans installed apps and organizes them into categories based on behavior. Under the permissions tab, categories include "track location" and "access contacts." Under the ad-detector tab, categories include "collect location information" and "show in-app banner ads."
The Application Management feature, accessible only if the app has administrator rights, lets you force-close currently running apps and see an app's size, memory, permissions and other statistics.
Most of this information is also available from Android's standard Active Applications menu. Still, all this data presented in one place gives you a better idea of how your device is functioning.
The SMS and Call Filter feature lets users create groups of phone numbers, and can block SMS messages and/or calls from numbers in a given group, or block outgoing calls to a given group. You can set blocks for certain days and times of day, useful if you don't want to get work calls on weekends or receive calls from your family after 11 p.m. Other mobile-security apps have similar blacklisting and whitelisting features, but Avast's was more robust and nuanced than any others we tested.
The app's Web Shield feature, accessed from the upper left-hand button on the home screen, protects you from malicious links when using the default Android browser, Google Chrome, Amazon Silk and Boat Browser; support is coming for the Dolphin browser, too. Every other mobile-security app we've reviewed offers Web protection only for the default Android browser and, sometimes, Google Chrome.
Other Avast features include Network Meter, which tracks data usage on 3G, Wi-Fi and roaming connections, and a firewall that can only be activated on rooted Android phones. Other security apps we tested lacked such features.
Web portal
Avast's main website doesn't have an obvious sign-in area; you'll have to go directly to my.avast.com. Once there, you'll find a whole lot of well-organized information about your device.
To send the device commands, use the drop-down menu at the top right of the page. Select the command you want and press Send.
Premium vs. free
The free version of Avast Mobile Security & Antivirus comes with all the malware-detection features, plus the ability to remotely locate, lock and wipe a device, and make it emit an alarm. Other anti-theft features, such as taking photos remotely and Geofencing, are premium-only.
You can see app permissions with the free version of Avast, but the ad detector is premium-only. Application Management, SMS and Call Filter, Application Locking, and Network Meter are all free. App, music and video backups are premium-only.
Verdict
Avast Mobile Security & Antivirus, with its attendant apps, offers a staggering number of features and customization options — so many that it might be overwhelming for new users. But once you get acclimated, Avast offers users unprecedented control over their devices' security, privacy and other internal functions. No other app we've tested has the breadth or depth Avast offers, from its anti-theft features (such as Geofencing or surreptitious photo-snapping) to more specialized features such as call and text blacklists, and its privacy monitor.
The only other strike against this app is that it scored lower on the AV-Test than the competition. If you want something simpler, then Lookout or McAfee might be the mobile security app for you. But if you want the full package, we recommend Avast.
