How to clean an Otterbox case?

About 3 weeks ago, I purchased a white Iphone as well as an Otterbox Defender case. The case is purple & white. Most of the case, which is white, is really dirty already. I was just wondering what I can do to clean it… Thanks in advance!
I mean, this case was 40$$, and I don't want to have to stop using it already just because the case is dirty.

I don't know how to put music on my iphone 4?

I would like to put my music from itunes onto my iphone but don't know how to do it. I'm not very good with technology, so I would need really basic step by step notes.
I do have an itunes account created, I also have music on my desktop that I have downloaded.
Now I would like to transfer these songs onto my iphone. But got absolutely no idea.
Can anyone please help me out?

Can i use an iphone 5 with a separate contract?

I currently have a blackberry and a contract which gives me unlimited data.

if i buy an iphone 5 handset (without a contract) can i just put my current sim into the iphone and be able to use internet, apps, apple store etc

Can I get a iPhone 4 for Straight talk mobile?

I've been wanting an iPhone, but Verizon is trying to make me pay 100 dollars a month! (60 for 2 gigs of data and 40 monthly line access) that's absolutely ridiculous. I was wondering can I get a iPhone 4 (Free at the Apple Store) and use it on Straight Talk?

Is the iphone 5 worth $100 dollars more?

So, i have my sprint upgrade at the end of the month and i was thinking of getting an iphone. I could get the iphone 4s for 100 dollars cheaper than the iphone 5, unless the iphone 5 is really THAT much better?

Is there much difference between the iPhone 4s and iPhone 5?

I've never owned an iPhone before. I've got a crappy little HTC Wildfire S at the moment that I really need to get rid off. I found a really good 24-month contract offer for the iPhone 4s on vodafone (300 minutes, unlimited texts, 250mb + 2GB Wi-Fi & iPhone for free) and I'm tempted to do it. From my own research there doesn't seem to be that many differences between the 4s and 5, except the obvious (slightly faster processor + bigger screen)
I actually prefer the design of the 4s/4, especially the back.

Owners of both the iPhone 4s and iPhone 5, what do you think?