Iphone pay as you go (monthly)?

Can't get iphone on contract so gonna get it on pay as you go which is monthly but don't know how iphones work? Do they waste credit, how much internet do you get etc etc. If you have an iphone please tell me abit about them

None of that has to do with owning an iPhone. If you get pay as you go your best bet is to get one of the tmobile plans. You may want to buy a used 4s unlocked to save money on the phone itself. I don't know what you mean by wasting credit, and the amount of data you receive is based off of the plan that you order.