ESET isn't a household name in the U.S., but the Slovak company was founded when the public internet was still in its infancy, and it's one of the biggest antivirus players in Europe, with more than 100 million users worldwide.
The company's Android app, ESET Mobile Security, offers excellent protection and a moderate system-performance impact. But its user interface is outdated, and many of the useful extra features are reserved for users of the premium version, which costs between $10 and $15 per year but offers some multiple-device pricing. It doesn't quite make our list of the very best Android antivirus apps.
Costs and What's Covered
Like many Android security apps, ESET Mobile Security is a "freemium" app that offers both free and premium levels of service, although everyone gets to try the premium version for the first 30 days.
It can be cheaper to buy a premium subscription directly through ESET.com ($9.95 for one year or $14.95 for two years) or the Amazon App Store ($9.95 for one year) rather than through Google Play ($14.95 for one year).
A company representative told us that customers who purchase through Google or Amazon can get premium features on up to five devices; those who buy the app through the ESET website are limited to one device.
Outside of Google Play, you can activate the premium features with an ESET account username and password, or an ESET-provided activation code.
ESET reserves a large portion of its functionality for the premium version of the app. If you opt to stick with the free version, you'll retain the antivirus and anti-theft features, but the latter functions will be accessible only via SMS text messages, as you'll lose access to the ESET web portal.
ESET also makes software for Macs and Windows devices; for more on those platforms, check out our lists of the best Mac antivirus software and the best antivirus software.
The malware-scanning function of ESET Mobile Security is quite robust, with three distinct levels of scanning. A Quick Scan searches installed applications, other executable files, library files and ZIP files to three nested archives (i.e., archives within archives within archives); it typically took 6 seconds on my Google Nexus 6P.
The Smart Scan adds external storage to the Quick Scan, so the added time depends entirely on the contents of your microSD card. Finally, the Deep Scan is what other apps call a Full Scan — it goes through all files on internal or external memory, regardless of the extension, and, in my testing, typically was done at just under a minute.
If you are using the free version of the app, the scans and updates to the threat database must be initiated manually, although Real-time Scanning and ESET Live Grid, if enabled, will still keep you protected from newly downloaded content.
The paid version of ESET Mobile Security adds the ability to set a time for a scheduled scan. By default, the scan will occur daily, but you can change that by tapping on the abbreviation for the day. Users of the paid version can also set a scan to occur only when the device is charging, which may be particularly useful for people concerned about performance or battery life.
If a threat is located during a scan, users of the free app will be asked to delete the threat, quite possibly an entire app, immediately. You can instead add it to the Ignore White List; paid users also have the option to quarantine the threat without deleting it.
ESET Mobile Security performed well in independent German lab AV-TEST's most recent evaluations of Android mobile security products, conducted in July 2016. It detected 99.9 percent of the 3,459 brand-new malware threats it encountered and an equal percentage of 3,367 samples of malware discovered in the previous four weeks.
This score edges ESET Mobile Security ahead of the curve. Among the 26 Android security apps evaluated by AV-TEST in July, an average of 99.6 percent of brand-new threats, and 99.8 percent of recently found threats, were detected.
Among the six Android antivirus apps we reviewed in 2016, this placed ESET behind Norton Mobile Security and Bitdefender Mobile Security (both of which scored 100 percent on each of the two tests) and Kaspersky Internet Security (99.9/100 percent), but ahead of CM Security (99.7/100 percent) and Avast Mobile Security (99.5/99.7 percent).
Some Android malware-detection scores jump around from one set of evaluations to the next, but not ESET's. Over a year of AV-TEST evaluations, ESET's score never dipped below 99.8 percent detection.
Security Features and Tools
Users of the free version of ESET Mobile Security & Antivirus have access to Remote Lock, GPS Location and Remote Siren via SMS. Commands can be sent from any cellphone, and require the command and the password you selected in the app.
Premium subscribers get a number of additional features. Chief among them are access to the Anti-Theft functionality on the ESET web portal, my.eset.com, as well as Proactive Protection, which will flag your device as missing if the app detects suspicious behavior. (Suspicious behavior includes repeatedly incorrect passcode entries, SIM-card removal or the revocation of administrator privileges from ESET Mobile Security.)
When you log in to the web portal and click the Anti-Theft tab, you will see a list of your registered devices. Clicking View Details takes you to the status screen for the device.
If your phone is missing or stolen, and Proactive Protection hasn't been triggered, you need to click the large red Device Is Missing button. The phone will lock itself and begin sending the GPS location, the IP addresses of any connected Wi-Fi networks and photos from the front and rear cameras. (It took about one minute for this data to come through on the site in my tests.)
You can also remotely activate a siren (which sounds at full volume even if the phone is muted), post a message to the screen of the phone or, as a last resort, wipe the device completely.
The device can't be turned off in this "reported missing" state. The screen will display a message asking whoever finds it to "contact owner." It provides the email address you entered during Anti-Theft setup, along with a list of trusted phone numbers that you chose during setup.
One final function isn't what I would consider an anti-theft feature, but is nevertheless useful. You can set the app to automatically send its current GPS location to my.eset.com if the device's battery hits "critical level" and is about to die. Another security app calls this feature "Signal Flare," which is apt.
The Anti-Theft features are quite comprehensive, and all worked as advertised in my testing. However, the web portal was laid out awkwardly, and the inability to just ping for location or trigger the siren without flagging the device as missing (and initiating the photo-taking sequence) seems odd.
SMS & Call Filter
Available to premium subscribers only, ESET Mobile Security's SMS & Call Filter does what it says: it lets you filter calls and/or SMS/MMS messages. But the latter function is not available to those using Android 4.4 KitKat or later — about 70 percent of the Android global market — or to anyone using the Hangouts app to handle text messages. (This limitation applies to rival Android security apps as well.)
Nevertheless, ESET had the most robust call and SMS filtering features of any Android security app that we reviewed. It took the ability to whitelist or blacklist numbers to an incredibly granular level. There was also a convenient "Block Last Caller" button for people who just got off a call they didn't want to repeat.
The rules let you either block or allow calls from individuals, groups or categories of numbers. If, for example, you don't want to hear from anyone except a handful of people between midnight and 7 a.m., you can create a list of approved numbers (or select from an existing group in your contacts) and then create a different rule to block incoming calls from all numbers. You can even create rules blocking outgoing calls, which may seem less critical, but parents may find it helpful if a child is prone to making calls at unfortunate times.
As with other aspects of ESET Mobile Security, the feature isn't the most visually appealing, but it gets the job done — in this case, with more options than any other app we tested.
ESET Mobile Security blocks known phishing sites and displays a warning message. This feature is available only with some browsers; the Anti-Phishing screen displays a list of your browsers indicating whether each is supported. On its website, ESET promises that Anti-Phishing will work with any browser pre-installed on Android devices, but notes that it's having a problem with Chrome on Android 6 Marshmallow.
I did not have good luck with the Anti-Phishing feature in my testing. Visiting a few known phishing sites produced no warning of any kind. If web protection is a primary concern for you, I'd recommend Bitdefender Mobile Security, Norton Mobile Security or Avast Mobile Security.
ESET's Security Audit feature is similar to the privacy-protection features on other apps — it offers advice regarding your device's settings and your installed apps to help keep your device running securely and smoothly while avoiding unexpected charges.
Device Monitoring is the first section of the Security Audit, and will flag things such as connections to open Wi-Fi networks, lack of free device memory or data roaming.
The second section, Application Audit, reviews installed apps and sorts them into categories (e.g. use paid services, track location or access contacts). Click on a specific app to go to the Apps page in the Settings menu. From there, you can uninstall the app or, for users of Android 6.0 Marshmallow and later, revoke individual permissions.
Security Audit's execution is very basic, but it will be enough for most people. Overall, the feature will make you more aware of possibly harmful app permissions.
Online Education (U.S. only)
Paid users of ESET Mobile Security have access to a series of videos on ESET.com designed to educate users on how to stay safe online. It's a nice extra, but the videos aren't available in the app, and most users will fail to seek them out.
To evaluate ESET Mobile Security's impact on system performance, I ran multiple tests using the Geekbench 3 benchmarking tool on my Nexus 6P running Android 6.0.1 Marshmallow. Following installation of the app, the phone scored 15 percent higher than its baseline average; during a full scan, it scored 4.6 percent lower than the baseline.
These results placed ESET Mobile Security in the middle of the pack of the six Android antivirus products we tested with regard to system impact, both post-installation and during full scans. ESET was notably closer to the top-end performers Bitdefender Mobile Security and Kaspersky Internet Security than to those in the second half of the group.
Setup and Support
ESET Mobile Security installed quickly from Google Play over Wi-Fi. As with some other Android security apps, ESET will do a full scan while it installs, which adds a couple of minutes to the process.
ESET lets users help themselves when it comes to support. There is a question mark in the upper-right corner of almost every screen in the app; it gives you an overview of every item on the current screen. I really appreciated this feature and found most of the answers I was looking for.
If you need more help, tap the menu button in the upper-right corner of the app's home screen and select Customer Care. Tap Customer Care again to send in a report form, or select ESET Knowledgebase to go to a FAQ web page. If the FAQs don't help, tap the Contact Us link on the top of that page, and you'll have the choice of sending ESET technicians an email, getting live chat support or trying your luck with the ESET User Forums. There's no telephone tech support.
ESET Mobile Security has perhaps the most basic interface of any of the six apps we tested. The main screen displays six large buttons to access the various features of the app; the upper-right corner of each button serves as a status indicator. If you have the free version of the app, each of the premium features will have a blue banner in the upper-left corner of each button.
Most of the features in the app are straightforward and intuitive, but if you are a fan of Google's recent Material Design aesthetic overhaul, or pleasing visuals in general, ESET Mobile Security may not be the best choice for you.
ESET Mobile Security offers a compelling set of features at a reasonable price, particularly if you purchase the app directly from Amazon.com. The free tier will meet the needs of some users, as it has excellent malware detection, a moderate performance impact and a few extras.
My biggest complaint regarding ESET Mobile Security is the user interface and overall look of the app. While ESET consistently updates the functionality of the app, the design looks and feels years out of date. The Anti-Phishing feature's failure to block known phishing sites also gave me cause for concern.
While the core functionality of ESET Mobile Security worked well, there are better premium options, such as Bitdefender Mobile Security or Norton Mobile Security, for those willing to pay for it.