hi I just seen the iphone 6 thing and I was wondering how much will it be if I got one but I got my cellphone in March. can anyone tell me how much will it be if I paid off my phone? (I got the 50$ student plan with a S4 Mini)
Depends on the cost of the device at the time you signed your contract and how much you paid to obtain the device.
The short answer is a set fee of your monthly service goes towards the total cost of the device. To exit your contract early you need to pay of the remaining device balance. A cell phone contract with a low up-front cost is nearly identically now to financing a purchase over 24 payments, only those payments are hidden in your monthly service cost.
Based on the current selling price of your phone it looks like you would need to pay around $375 in cancellation fees. The lowest upfront cost for the iPhone is around $200. This means to change to the iPhone 6 at launch you are going to be out of pocket for around $575.