Upgrading jailbroken IOS 5.1.1 to 6.1 iPhone 4?

I've iPhone 4 jailbroken on IOS 5.1.1. Now that we can jailbreak IOS 6.1 using evasi0n. Please advice is this worth to upgrade the device to IOS 6.1 and jailbreak again? Is there much difference between IOS 5.1.1 and IOS 6.1?

Stolen/lost iPhone 4 i their way it's technically stolen?

How can i prove a phone is mine if they cleared all the data and the only thing i know is that the back of the screen is broken… I lost the phone yesterday and then on Craigslist they put a add on it today and i believe its my phone because they said cracked screen… This phone was giving to me by someone so any other info i can't get… Now i believe someone stole the phone from em when i was in the store talking a sales person i must have placed it down and got distracted and i think they snatched it:/ the only other place i could have lost it was on the bus… What should i do?

Added (1). I do not have the box or anything. I was hoping their are other ways to get info about the online or other ways unfortunately i didn't take the time to add locks and other things. I was hoping their was something in the phone that you can put that will never change even if reset…

Why won't itunes let me sync my iphone?

I just added my iphone to this computer and authorized it and everything. It is authorized on 4/5 computers. I have added one song to my list and when i go on 'file' then 'devices' then 'sync' and other options i'm unable to click on it, and its a lighter colour? Why is it like that and how do i change it so i can sync my iphone and its music?

Instagram on my laptop or on Scope?

I used to have internet Access on my iphone over the summer time, so I made an instagram way back then. Then my dad took internet access off of my phone because it was costing us too much money, so basically I had to abandon my account. So finally, I discovered an app for Kindle Fire called "Scope" Which allows you to access your instagram account through your Kindle fire and you can still like and comment on stuff. So last night I got on instagram for the first time in months and I was so excited to see my account and look at my friends photos and stuff. Then my mom told me that I could get on instagram on my laptop as well, so I went online, and sure enough I can access instagram on my laptop as well. But I haven't found out how to add any photos or update my profile picture on my laptop or Kindle Fire… How do I do that?

Can Sprint blacklist my iPhone ESN that I purchased elsewhere?

I had my phone number ported to Sprint in August of 2011 and purchased an Evo 4G through Sprint. I recently purchased an iPhone 4 and switched out my existing Evo. I want to leave Sprint but I will leave behind a small bill plus a very small ETF (I only have 4 months left in my contract). Now before you all get into the negatives, I just want to know will Sprint blacklist, or give my iPhone a bad ESN if I do this? Would it just be easier to swap my Evo back in place then leave? I ask because it took Sprint half a day to properly update my iPhone. I'm not worried about my phone number because I left T-Mobile with an ETF (which I paid off eventually).

BTW if your wondering why I plan on leaving like so, its because SPRINT SUCKS! They have the worst iPhone coverage. My iPhone speed is like the old AOL dial-up. My sister lives with me and she has the exact same iPhone 4 on Verizon and she can watch a Youtube video on 1 bar; I can only hope to load Youtube with 4 bars on my phone. There are other issues with billing and coverage, but I'm fed up with Sprint.

Also, I asked about blacklisting because I bought that iPhone. If I decided to sell it to someone or eventually pay off what I owe and come back I want to have my iPhone as an option.

Using a 100-240v Iphone Charger at 220v?

This may be a daft question BUT
Will I be ok to use my UK Iphone charger in Greece (where the voltage is 220v) without a converter/transformer

Obviously i will need an adapter
I just wanna make sure my phone won't break!

It it worth buying the iPhone 3GS?

I'm currently on the Samsung Toco Lite and I want to buy and iPhone. I can't afford the iPhone 4 and I can just afford the iPhone 3GS NEW from eBay. I was considering getting the Samsung Galaxy Ace but I would prefer and iPhone.
Some people have said that it can't be updated but other people have told me it can be updated to to iOS 6.Is the iPhone 3GS still worth buying NEW.

I'm trying to sell my iPhone?

I noticed on eBay the prices are a little more than what I can sell it for on Craigslist. It's a little scratched on the metal on the side but the screen has a cover and is not scratched at all. On Craigslist I'm also getting bugged by resellers offering me around 350. I called apple and asked if they can replace it cause it has apple care but I don't have the apple care plus. Any suggestions