I look at it this way -
Last quarter of 2012 there were 32.8 Million infected Android devices
First quarter of 2013 there are 44 Million reported maliciously infected Android devices.
The problem with Android and the Google world is that it is open and un-policed by anyone.
So the scum of the world write malicious code just to see if they can do it and put it up on the store unchecked by anyone.
You see a "looks cool" app and your screwed.
The other issue is operating system and applications associated with them, Google creates a new or improved version of the current operating system and the manufacture of the phone needs to decide if THEY want to release the system for your revision of the phone.
Most manufacturers can't be bothered to check all their old phones to see if there compatible, and then will your older app work with the newer operating system, and then who does the operating system get in to your device?
Some push them weather you want it or not, some make you find them on their web site some put them in the app store - all up to you.
How tech savvy are you?
Apple does have a nanny operating environment, but they do police their applications, their developers, their operating system.
If they release a new operating system they have checked it with the available working hand sets.
They tell you on your phone a new one is available.
For me that's a big plus. No malicious code.
Another thing between them, an Android device is controlled from the device, so if you nuke your phone/tablet there may be o recovery option for you - and the part that makes it a PHONE (the BIOS in computer speak) is fully accessible on an Android device where as an IOS (Apple) device has a protected area that a user REALLY WANTS to access is a P I T A to get to, and even then should you get in there, iTunes can access it's primal brain and reset the deice and also (they say) from the free-for-IOS-users iCloud service.
Mind you, I still own a stupid phone form 2007 - I too am in the process of learning about current generation smartphones, I too was very pro-Android until I started researching the Pros/Coms of each operating environment and for me I have decided on the Apple world (which also helps as I have a large amount of already purchased material on iTunes - but I did try not to let they influence my decision)
I just like the fact that only ONE KNOWN malicious application EVER made it in to the Apple environment (iTunes) and that was in 2010 and lasted for 13 days before Apple pulled it.
(It was a bit of code to drain the battery faster than normal)
Ultimately it is your choice, but I have settled on the Apple environment - I just am waiting on the release information on Apples competitors to the S4 which may be called the iPhone 5s or iPhone 6 due out in June/Aug time frame - before I buy a iPhone 5 or the new one.