That's some good news!
Any idea as to whether the gmail app scans for viruses? Seems crazy to me that the desktop version would and the app wouldn't, but I'm not really an expert...
Not that attacks on Android aren't increasing, but compared to Windows platforms the number is quite small. I have had two Android smartphones, use the Gmail app on both, and have never felt I needed an antivirus on my Android device.
I don't know that the "client side," meaning your Android Gmail app or the web interface on PCs does any virus scanning. That has always been a function on the server side. I have uploaded several huge files to Google Docs and when people attempt to download them Google Docs tells them that the files are too large to be virus scanned, which strongly suggests Google does this on the server side. Of course, those specific files were virus scanned I can't begin to count how many times before I zipped them up and uploaded them. I always tell those that they will get this warning from Google and that these have been virus scanned before they were ever uploaded.
As others have already mentioned, most issues occur only if and when you actually open an attachment, not at the moment of download. There are exceptions, but they are rare, and if Google is doing scanning on the server they've already been checked.
In the end, you best defense is "knowing the source" and knowing that source to be trustworthy. I can't even count the number of attachments I've received over the decades from many sources, but I knew all of these sources, knew that they had antivirus on their computers, knew that I had antivirus on mine, and that the probability of infection was small. It's no coincidence that I've had virtually no infections (I think none, but I can't remember if the few issues that have occurred over the years in my household were strictly my partner's machines or involved my own - that's how infrequent any have been) because I never open attachments from individuals or organizations that I don't know and trust.
Addendum: This Google support page entitled, Anti-virus scanning attachments, pretty much confirms that scanning is a server-side function and happens more than once.
Edited by britechguy, 28 January 2016 - 08:05 PM.