Microsoft Defender logo.

Microsoft’s antivirus tools for Windows have changed a lot over the years. The “Defender” branding has been used for a number of things—now it’s even available for Android, and iPhone. But what the heck does it do?

In June 2022, Microsoft Defender became a cross-platform app. This is not the same antivirus tool you may have known as “Windows Defender,” though. The scope of what Microsoft Defender does has changed quite a bit. Let’s take a look.

A Brief History of Microsoft Defender

As far as Microsoft services go, Defender has one of the more convoluted histories. It was originally a rebranded version of a tool called “Microsoft AntiSpyware,” which was first available on Windows XP in 2005.

Later in 2005, Microsoft AntiSpyware became Windows Defender. This was technically the second beta of the tool, but the first one with the Defender name. It was a pretty basic antispyware suite of tools, though Microsoft removed some of the tools from the first beta.

In 2006, Windows Defender left beta. It came pre-installed on Windows Vista and Windows 7 as the default antispyware tool. In Windows 8, Defender gained antivirus components, replacing Microsoft Security Essentials for Windows. It’s now the default antispyware and antivirus tool in Windows.

Nowadays, many of the tools previously associated with Windows Defender are found under the “Windows Security” settings. The “Defender” moniker doesn’t show up as much.

RELATED: How to See What Malware Windows Defender Found on Your PC

What Is Microsoft Defender for Android and iPhone?

Microsoft Defender images on iPhone
Microsoft

Microsoft Defender is now a two-pronged suite of tools. There’s the antispyware and antivirus components, which are baked into Windows. Then there’s the cross-platform component, which is available for Android and iPhone (as well as Windows and macOS.)

(Microsoft does offer “Windows Defender for Endpoint” software that includes antivirus on macOS and Linux, but this is for organizations and not consumers.)

On the most basic level, the cross-platform Microsoft Defender app is sort of a dashboard that allows you to keep an eye on the security of all your devices. You can check the security of your laptop from your phone, for example. It works with the existing antivirus software on the device to give you information about your protection.

However, on some platforms, Microsoft Defender can act as an antivirus tool itself. The Android app can scan for malicious apps and scan links for phishing, but that’s not possible on the iPhone. The mobile apps can also scan network traffic.

There’s one really big catch with Microsoft Defender—you need a Microsoft 365 subscription to use the dashboard app. It’s included with the Microsoft 365 Personal and Family plans. You probably don’t need antivirus on your Android device, but Defender is a solid choice if you already use it on Windows.

RELATED: Does Your Android Phone Need an Antivirus App?

Should You Use Microsoft Defender?

Microsoft Defender on a PC and Android phone
Microsoft

In all honesty, Microsoft Defender for Android and iPhone is probably not very useful for most people. Those platforms already have tools in place to keep your phone safe. Android devices have Google Play Protect, while iPhones have Gatekeeper and Protect.

That being said, if you have a Microsoft 365 subscription, it’s free and there’s no harm in using it to keep tabs on your devices. Microsoft has also committed to continue to add more features in the future. Things like identity theft protection and secure online connection.

At the end of the day, this form of Microsoft Defender is a bit of a strange product. It’s not yet clear how useful it will be, but it might be worth checking out.

RELATED: What is Google Play Protect and How Does it Keep Android Secure?

Profile Photo for Joe Fedewa Joe Fedewa
Joe Fedewa is a Staff Writer at How-To Geek. He has been covering consumer technology for over a decade and previously worked as a News Editor at XDA Developers. Joe loves all things technology and is also an avid DIYer at heart. He has written thousands of articles, hundreds of tutorials, and dozens of reviews.
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