What does a data plan do for an iphone?

Like can i buy and download apps and get itunes for music? And can i use internet through my house like my ipod does? Does not having the data plan you can't have a phone at all?

Let's say you are not at home, and not in any area with Wi-Fi access. You want to access the internet, check your mail, download apps and music on the fly. For that to happen, you need a dataplan.

Want to send text messages? Need data plan.

However, if you are by a wi-fi hot spot all the time, then you can use the Wi-Fi and do everything I just mentioned above, and save yourself money.

Carriers require you to sign up for a data plan when you buy a "smart phone" such as the iphone. When they sell a smart phone, they sell it at a discounted price, while they make up for that buy the charges they make for data plans. As far as I know, unless they have made some drastic policy changes, they will not sell you the phone without signing you up with a data plan. You can use wi-fi all you like, which is good because it will cut down on your data usage, but a carrier still won't sell the phone minus a data plan.

A data plan does two things.

1- You get internet access when not on a Wi-Fi network/hotspot. On older phones, you could do a pay-as-you-go service, but smartphones use a lot of data and are checking with it constantly, so it's cheaper to do some sort of plan.

2- It helps subsidize the price of the phone; that's why you pay $200 for a $700 phone (you're paying $10 per month of the data plan towards the cost of the phone).

You can get a phone without a data plan, but you'll have to pay full prices (3 to 5 times price of the phone). You can use it on Wi-Fi to save on any data plan quota, to save the data for use when you are not on Wi-Fi.