What to do before selling Iphone 4S?

I want to sell the iphone at Gazelle.com but am I supposed to do something before I sell it? Like do I cancel my phone plan or what exactly do I do before I sell it? I'm obviously gonna get the Iphone 5: D

What's the data limit for Straight Talk's Unlimited plan?

I'm probably going to buy the unlocked GSM iPhone 5 and then use it on Straight Talk.

However, has Straight Talk said how much data you can use before your data speeds start getting throttled? Also, will the data that I use while I'm on Wi-Fi count against that data limit?

Switching from 3G Droid X to 4G iPhone 5 on Verizon, can I keep the unlimited data?

If I buy the iPhone 5 at the unsubsidized more expensive price, can I still keep the unlimited data plan when I switch from my Droid X that uses 3G? Does going from a 3G device to a 4G one negate this loophole or can I still sneak by and keep my unlimited data plan?

Also, is it true that since I don't renew my contract, thereby being totally off-contract, could Verizon just decide one day to take the unlimited data away at any time and force me to renew the contract with tiered data?

Lastly, at what point in the unlimited data usage does verizon decide to throttle users?

Verizon user: Can I switch from Android to iPhone 5, when the iPhone 5 comes out?

I'm a Verizon user. The iPhone 5 is so slick and perfect! I really want to switch my DROID RAZR phone to the iPhone 5 when it comes out, but I don't know if I actually can. I have a two-year contract. And if I gotta pay to switch my phone, I'm payin'!

Added (1). Don't tell me DROID RAZRs are better! I've always been an iPhone fan, you don't know how I feel with my DROID RAZR! LOL.

Added (2). Someone tell me how much I gotta pay!

Added (3). Btw fyi you can't insert sim on an iPhone… It's basically cmda

How much do you pay monthly for your iPhone data? (Verizon)?

I'm considering getting an iPhone 4s maybe when the price drops due to the iPhone 5 coming out soon and was wondering what the average monthly costs are for the data? I'll be pretty much the only smart phone user in my family plan. (My parents have 2 basic phones). I'm looking to get probably the cheapest data package that still gives me plenty of data. (I don't think I'll use more than 2gb.)

Will you be able to use the iphone 5 with straight talk from walmart?

I heard you can do it with a sim card is that true? If so where can i get a walmart sim card? Do i get it from the store or online?

Added (1). Yes you can put a sim card in it. I have one in my iphone 4s but i don't know if it is on the iphone 5 and if i buy the iphone 5 from at&t i shouldent have to unlock it right? Thats how the 4s works. If its at&t it doesn't need unlocking

Can I sell my iPhone 4s if I do an early upgrade?

I currently have an Iphone 4s, I'm under contract until June 2013. Can I sell my iPhone but keep my contract and just put my sim card in another phone that is already paid for?

I'm wanting to get cash for my iPhone, although its looking like i might be better off selling my iphone for $285 back to apple so that I can upgrade to the iPhone 5!