Popularity isn't always a good thing

You can always tell in the computer world what the most popular device or what the most popular software is just by the amount of viruses/malicious files that crop up. For example, windows isn't any less secure than Linux or mac; despite what nerds claim.

It's the fact that the more users there are,  the more people to steal credit information, to spam and to generally piss off. And when there is a will, there is ALWAYS a way.

It probably doesn't need to be said, but Android clearly has more users than iPhone's IOS, quite a few malicious files are cropping up taking credit off of phones and stealing personal data. Not so musch on IOS.

You could say though that IOS is more secure, just by the fact that you are not allowed to do anything with it other than what apple tell you. With android though you can add any software you want as long as you select the option to do so.

Secured or not, people have to be care full of the things they install on computers or phones.

As for windows phone, never used one so I don't know much about them. But again: it won't be any less secure than Android or IOS. If it ever did become the dominant product in smart phones you would see allot of malicious start to appear.