I am looking at buying a fefurbished ipad retina from the Apple Store. I am wanting the 32 gb wifi Verizon 4g model. I currently have unlimeted data on my verizon iphone, and dont want to switch to the shared data plan at this time, but may want to in the future. If I buy this ipad from the apple store, am I locked into anything from Verizon? I am hoping to just use it in the wifi mode mode for a while.