Why does my iPhone device not show up on any computer?

When I used to plug my iPhone into a computer, the device would pop up on the computer screen automatically, or show up in the "my computer" folder and I was able to upload and edit photos saved in my phone, without the use of iTunes. This no longer happens. Now all the phone does when plugged into a computer is charge. What do I do? I do not know whether it is the public computers I'm using or my iPhone itself? I'm unable to use my own laptop because it is broken. Help Please! >_<

Added (1). I can use my flashdrive device on these computers (most are of colleges, universities, and a friend of mine's), which can upload the same stuff… So what's the difference? And I said that I used to upload from my iPhone before, which was only some months ago… I don't think a restriction would have been put on that quickly, do you?

I'm thinking of listing an iphone on ebay?

Its a one week old verizon 8GB black iphone4. 0 scratches, HD screen protector on it, and comes with 2 cases. How much do you think I could get for it if I listed it as an auction? Btw it has clean esn

Added (1). I want atleast $200 for it for everything listed. Fair?

How much battery life is 5200 mAh?

I want to buy a portable charger for my iphone 5, it says its 5200 mAh what does that mean? And do you recommend 5200 mAh or a 2500 mAh?

Buying something on eBay with false info?

Ok so if I bought a iPhone 5 on eBay and the seller said its in good condition but doesn't except returns. And when I receive the phone it doesn't work or is not working property. Is there anyway I can return and get my money back or something? Isn't that a law?

Is my iPhone 5 eligable for a replacement?

I have a one year warranty, and my iPhone has recently shown a defect. The top button only works half of the time. It will click down but nothing will happen. There's also some wear and tear from usage.
Does anyone know?

Iphone not connecting to my house Wi-Fi?

I have an iphone 4 and lately it hasn't been connecting to my Wi-Fi. Everyone else's phone will connect and when my friend stays over, her's also connects. It just seems to be my phone. Any suggestions?

My iphone fell in the jacuzzi

My phone fell in the jacuzzi and i took it out after like 10 seconds. I tried turning it back on but it wouldnt turn on. There was a light on at the back of the phone, but my friend tried to shake the water out and the light turned off. He put it in a bowl of rice and its been in there for about an hour. Did it break? I had to beg my parents for an iphone and they will never forgive me for this.

Should I Upgrade To iOS 7 or Keep My Jailbreak iOS 6.1.1?

Should I Upgrade To iOS 7 or Keep My Jailbreak iOS 6.1.1?
I have a iPhone 4s Running iOS 6.1.1 Jailbreak with 30 Jailbreak Tweaks and I Saw iOS 7 and it look very nice so should i Upgrade Yes or No. Please Answer As soon as possible.