FORTUNE — As a long-time Apple (AAPL) user who doesn’t spend much time worrying about viruses, trojans and other malware, I’ve never had a lot of confidence in the reports issued periodically by computer security companies. They always seemed to be in the protection racket, trying to scare users into buying their anti-viral software.

But a pair of recent reports got me thinking.

The first, from McAfee — now an Intel (INTC) company — shows an pretty astonishing rise in malware designed to attack mobile devices, from 792 samples in 2011 to 36,699 in 2012.

Perhaps not surprisingly, given its growing popularity and vaunted openness, 97% of those samples were designed to attack Google (GOOG) Android. See Mobile Malware Growth Continuing in 2013.

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