IPods are music and video players. ITouch is the mini version of IPad. Iphone does everything the ITouch does and is a cell phone and has internet service all the time. You need wireless service added to any Iphone but you dont' need it for ITouch. ITouch picks up any free wireless network in the area. Iphones and ITouch uses apps, they are thousands of free ones and thousands of them that cost about .99 or more downloaded to your IPhone or ITouch or IPad. IPods play music and/or videos you download and install on them using a computer.