IPhone vs Android. Opinions?

I'm planning on getting a new phone soon, because my current phone (iPhone 4) is having some issues and my lock button is broken. I was just wondering what people's opinions are for iPhone v. Android? I've used iPhones and I'm used to that, but I've also heard really good things about Androids so I'm curious.

Android. More open source. Customization, more free apps, most are bigger, and I love the Play Store.

Totally agree with budder

Get android. You can pretty much customise anything to your liking like the lockscreen and the GUI. You can download these and widgets from the play store

With Android you have to deal with viruses:
---
F-Secure, an anti-virus software producer, has released a report that details the saturation of malware content in mobile devices, and it turns out, Android platform was responsible for a whopping 79 percent of all malware intrusions in 2012. Android was also host to 96 percent of the intrusions in the fourth quarter alone.