Lookout provides a useful security app for both Android phones and tablets, along with a user-friendly website. It doesn't offer as many features as some security apps, but what it does provide is solid. It offers remote locking and wiping, but only if you use the premium service.
Symantec
Price: Free
Other versions: Norton Mobile Security ($29.99/yr.) adds anti-theft and anti-loss features, phishing protection, call and text blocking
Norton Mobile Security Lite provides free malware protection and remote locking. The premium service ($29.99/year) adds browser protection and call and text blocking, along with remote locating, a remote alarm, remote camera control to take snapshots and remote wiping. There is a tablet version ($29.99/yr.) coming (the date hasn't been announced) that will support the remote anti-theft functionality for Wi-Fi-only devices as well.
In addition to performing malware scans on app downloads and updates, you can run app and SD card scans on demand or schedule scans daily, weekly or monthly. Though Norton checks for virus database updates weekly by default, it can be changed to daily (or monthly).
By default you won't see an icon in the notification bar or menu unless the app detects a security issue, but you can enable it so you always know your security status.
Norton Mobile Security Lite has a very simple and straightforward interface. Unless you purchase the premium service, there are only two main shortcuts accessible on the main screen of the app: one for the anti-theft and another for anti-malware. But hitting the device's Menu button gives you a few more shortcuts, such as to view the activity log or access the update or notification settings.
The remote functions for the free version can be initiated only via SMS commands. The premium service offers a plug-in for the app that in turn lets you perform remote functions on your device using a Web browser. The free version lacks any SIM card protection or remote change notifications.
Bottom line
The free version of this app is the most basic of the five I reviewed. Norton Mobile Security doesn't offer as much as other free apps; you get much more if you sign up for the premium service, which comes at a recurring cost. That premium service does offer remote camera control, but most of its other features are available in other free apps.
NQ Mobile
Price: Free
Other versions: NQ Mobile Security Premium ($7.99/3 mos., $12.99/6 mos., $19.99/1 yr.) adds remote security features, anti-eavesdropping, financial data protection
NQ Mobile Security provides free anti-malware and browser protection, a firewall, cross-platform contact backup, and remote locating via Google Maps. It also offers a free privacy advisor that analyzes apps and their permissions, a traffic monitor that tracks data usage, and an app optimizer and manager.
SIM card change notifications are provided with the free version and can be set up to send to a specified mobile number -- say, of a friend. The premium service ($7.99 for 3 months, $12.99 for 6 months or $19.99 for 1 year) adds automatic virus updates and a remote alarm, along with remote locking and wiping. It also adds a malware scanner designed to scan banking apps, and anti-eavesdropping protection to help prevent phone tapping by any malicious apps.
Although the app installs on both phones and tablets, some features such as the remote functions won't work on tablets without SMS capability.
In addition to auto-scanning apps for malware when you download them, you can run full scans on apps manually (SD card files not included) or schedule a scan for every 7 or 15 days. Contacts can also be backed up manually (or automatically when you're connected via Wi-Fi).
The NQ icon sits on the notification bar and menu; it displays your status and data usage, and lets you quickly open the app. Once you open the app, you'll find a user-friendly and easy-to-navigate interface. The main screen displays your security status and shortcuts to each of the core features. Tapping the device's Menu key lets you access the settings, logs and other shortcuts.
The remote functions can be initiated via the Web or via SMS commands. The website lets you manage backed up contacts and view your security logs and status. It also offers a calendar feature that can sync across your devices and Google/Outlook calendar. Unfortunately, though, the site's interface isn't optimized for mobile access.
(Note: According to the website, NQ Mobile is the international brand of NetQin Mobile, and as a result, some parts of the app, help pages, etc. may carry the NetQin branding.)
Bottom line
Given that the free version of this app doesn't provide automatic virus updates or a remote alarm, locking or wiping, I would only recommend using the premium version, which comes at a recurring cost. Additionally, the premium version adds just two extra features (financial security and anti-eavesdropping) that other free apps don't usually provide.
Conclusions
Though there's certainly Android malware out there, your chances of becoming infected are still very low at the moment -- but they're even slimmer if you install an anti-malware app.
Incidentally, since failing batteries are the bane of many smartphone users, you might be wondering about the resource consumption of these security apps. During testing, all five of the apps consumed about the same amount of RAM on average when idle: 9.5MB to 11.5MB. And if you're concerned about how much space the app will take up, AVG had the lowest (0.71MB), followed by Avast and Lookout (both 1.81MB), Norton (3.83MB) and NQ (4.73MB).
If you're looking for a free security app, most of these have something to offer. AVG has a lot of features and an unbeatable price if you want to upgrade, but the app could use a facelift. Lookout doesn't offer as many features, but provides solid functionality and service.
NQ includes cross-platform backup support, but lacks free automatic virus updates, and while it provides free device locating, there's no alarm, which most of the others offer. Norton is the most basic free security app of the five, allowing only free remote locking in addition to its anti-malware features.
I was most impressed with Avast Mobile Security. Though it doesn't offer a Web interface or full tablet support, the free app includes some very useful features not found elsewhere, such as better uninstall protection, and is a must-have for rooted devices.