How much data is needed to use facebook on an iPhone?

I want an iPhone and only want to use data for Facebook. How much data is needed to use Facebook only? I check the news feed five or six times a day and upload a photo maybe once a day and never upload videos.

Is it worth getting an iPhone 3GS?

They are sitting around $230 NZD, whereas the iphone 4, and 4s are sitting around $400-$550 NZD on trademe. (like ebay). I need a smartphone, but want a half decent one thats cheap (ish) too. Is it worth getting a 3GS now that the 4, 4s AND 5 are all out? I don't care about being 'cool' and having the latest one, just need to know if its any good!

New itunes won't sync music correctly?

I downloaded the latest version of itunes and i see a lot has changed with appearance. Anyways I have a iphone 3g that i use as my ipod, and have never had problems syncing music too. When i clicked sync on the new itunes it says that it is syncing but when i check my iphone, the newer songs aren;t on there. Then i deleted some songs but when I synced they were still on the iphone after the sync. I don't understand why this is happening can someone please help me out?

How much data does iMessage use?

I have 300MB of data per month. Inreally don't want to go over. I send between 3000-5000 texts a month, not all to people with iPhones. How many iMessage texts could I potentially send on my plan?

How to delete aps, not used, on my iPhone 4 that is up-to-date on software?

I have iOS 6.0.1.In my apps tab on iTunes, I have the option to delete apps I have running on my iPhone and install apps that I do not have running on my phone; how the heck to I get rid of these stupid apps that I did not like and would like to get off my phone? (these are apps that do not show on my iPhone, only in iTunes). Also, I would like to install the update for my Starwalk app, but it states, "You must connect to a Wi-Fi network or use iTunes on your computer to download "Star Walk" TM - 5 Stars Astronomy Guide", but I can't find any option through iTunes to do so. How the heck can I download this new update through iTunes? I would assume it would be the same, route or avenue, as downloading any app's update through iTunes. Thanks

Added (1). Please do not tell me to HOLD DOWN ON THE AP AND PRESS THE X read my entire question please.

Can the apn settings be edit on a iphone?

I'm planning to get a iPhone and use straight talk as the carrier. I'm wondering if the some setting on a iPhone can be edit so that the phone can use web and send multimedia, along with reconfirm and calling.

Added (1). I'm wondering if the 'apn' not "some"

My music isn't working on my IPhone?

My IPhone 4 got an update, and then all of my music erased. When I plugged it back into my macbook pro, it said i needed to also update my macbook software, so I did. After that, none of the music could play. All of them apparently synced, but it took virtually no time, so I don't think they loaded. The songs are all on there, but they're a faded gray, not bold black, and I can't click on any of the songs. I tried syncing again, and only 4 songs synced, and were playable. I tried to remove the songs that aren't working, and I can't delete any. I tried to unsync the phone hoping it would remove the songs that don't work, but it only took away the songs that did. Help please! I need my music back on my phone. My apps all work and sync. Just the music is messing up right now.

Help on replacing iPhone 5 glass panel?

I bought a iPhone 5 glass panel because there cracks around the home bottom but the screen is fine. But there's only guides on replacing screens with LCD+Digitizer. So I need help on placing everything on my old screen onto the new glass

Added (1). This is the only thing I bought( and the kit to take things apart)