IPhone 4s MMS Messaging won't work

My iPhone 4S I have never had an issue with. Last night I was deleting a bunch of apps and then went to send a video and picture out to my friend. It took forever for them to send. The text messages went through with no issue. The videos not so much. So I turned on and off my MMS messaging, my iMessage, reset my network.still nothing. In the meantime, now I can't even send pictures. Randomly happened. Is it one of the apps? I need help, please.

Added (1). It is AT&T.
I deleted iTunes U… If that has anything to do with it. I deleted it on the phone though. And a couple of photo editing softwares. I've had my phone since the end of May and now this all happened. I don't want to reset my entire phone because of the conversations I have on it.

Added (2). It is AT&T.
I deleted iTunes U… If that has anything to do with it. I deleted it on the phone though. And a couple of photo editing softwares. I've had my phone since the end of May and now this all happened. I don't want to reset my entire phone because of the conversations I have on it.

What iPhone apps do YOU recommend?

What iPhone apps do you guys recommend?
I already have Wattpad, Songza and League of Legends data base.
I'm a 16 year old girl.
I'm not interested in twitter, instagram or things like that.

Added (1). And just because I'm a giirl doesn't mean I'm into things like Soroity or dressup games, eww! But I do like games like surviving highschool haha

Added (2). And assassins creed

How to inactivate a sprint iPhone?

I recently bought a phone from someone on Craigslist, Jennifer. She's a student and only had the phone for a couple days & I trust her. I bought the phone as a present, and just now gave the present. When they went to activate the phone under their own Sprint account, they were told that the phone has not been disconnected under Jennifer's name. I was able to make calls using Jennifer's phone and under her number. I'm assuming the ESN is good, or else it wouldnt have been able to call my cellphone. Seeing as i can't call her and don't have other contact information for her, how do I get around this? Can i disconnect the phone myself?

Upgrading to an iPhone 4, but want to keep the same number?

Yesterday i upgraded my phone to an iPhone 4. The guy from T-Mobile said that i could keep my old number from my old phone. (LG Optimus) The iPhone arrived today, without an Micro Sim card. The LG Optimus sim card is a normal sized sim card and will not fit. So i'm left with needing a micro sim card for an iPhone 4, but i want to keep my old number. What shall i do? I also need the sim card to activate the phone. Does the micro sim card come separate in delivery because it has personal details? Help would be appreciated. Thank you. (The iPhone was delivered from an out sourced company, not T-Mobile themselves)

Added (1). I upgraded early. I bought out the rest of the contract. But i can still use my Normal sized sim card in my LG.

My iphone 3g the Wi-Fi is not working?

I have an old phone the 1st gen of iphone, i used to have a Wi-Fi on my setting but now it won't allow me to do so, even my software is uptodate. Please tell me how to fix it or if you have any suggestion to fix it, ty

Do I need to own a Macbook to use an iPhone?

I know this is a pretty silly question, but I was wondering if I needed a Macbook if I have an iPhone? My dad's buying me an iPhone as a late high school graduation present, and it's the first time I'll be owning one. But, my laptop isn't a Macbook, and I was just wondering like if I plug in my iPhone to a non-apple computer, would it still work perfectly? Would I still be able to download easily?

Sorry if this is a pretty stupid question but thanks.