Can i buy a iPhone 4 without buying a plan?

I have a iPod 4 that i use with just Wi-Fi and i want to buy a iPhone 4 on like amazon so i can do more but i want to just use iMessage and stuff i don't want a monthly payment for cell service and data. Can you do that can you just buy an iPhone with no cell service or anything?

Yes you can. My cousins have iPhone 5S's with no SIM card in it. They use it just like an iPod.

Why not just get an ipod touch, that way you can get new.

Yeah it will cost a lot though