Apple isn't happy about the amount of Mac malware out there

And that's the reason Apple must keep iPhone, iPad and other mobile products behind the App Store's walled-garden, according to a top Apple exec.

A top Apple exec has said that Mac malware has now exceeded Apple's level of tolerance, and framed security as the reason for keeping iPhones locked to the App Store, during testimony defending Apple in a lawsuit with Fortnite maker Epic Games.

Apple's head of software engineering Craig Federighi told a court in California that Apple found current levels of malware "unacceptable". 

"Today, we have a level of malware on the Mac that we don't find acceptable," he said in response to questions from Apple's lawyers, as ZDNet sister site CNET reports.  

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Apple is defending its practices after Epic Games filed a US lawsuit against Apple because the iPhone maker kicked its Fortnight game off the App Store after Epic put in place a direct payment system for in-game currency, which would bypass the 30% fee charged by Apple to developers. Epic says Apple is too restrictive. 

The Apple-Epic case commenced on May 3. Yesterday, App Store boss Phil Schiller emphasized the App Store was focused on security and privacy from the outset. 

Federighi said that since last May, there have been 130 types of Mac malware – and one variant infected 300,000 systems. 

He added that Macs have a "significantly larger malware problem" than iPhones and iPads, comparing the Mac problem to an "endless game of whack-a-mole". 

Macs can install software from anywhere on the internet whereas iOS devices can only install apps from Apple's App Store.  

US security firm Malwarebytes, which sells Mac antivirus, reported that Mac malware was now outpacing Windows malware. But the company also noted that the threats to Macs, mostly adware, were not as dangerous as malware for Windows.  

Per 9to5Mac, Federighi compared the Mac to a car whereas iOS was designed with safety for children in mind. 

"The Mac is a car. You can take it off road if you want and you can drive wherever you want. That's what you wanted to buy. There's a certain level of responsibility required. With iOS, you wanted to buy something where children can operate an iOS device and feel safe doing so. It's really a different product," he said. 

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Federighi also contended that, if Apple allowed iOS users to sideload apps, things would change dramatically. 

"No human policy review could be enforced because if software could be signed by people and downloaded directly, you could put an unsafe app up and no one would check that policy," he said.