Hi, I have a two year family contract plan and I'm currently using a iphone 4s, or was. However I have dropped the phone and now I can't use the phone because the digital screen under the glass is messed up. I was wondering if I could buy a new smart phone (thinking about the LG v10) and adding it to the plan by replacing the iphone 4s. If I buy a new phone I would have to buy it at the full retail price, right? Also my plan doesn't end untill next year. Thanks