I am a senior citizen who is not very tech savy. I want to purchase an iPad with retina display and cellular. I have been reading all the problems people have had with Verizon when they want to cancel their monthly service. I don't know if it is worth the aggrevation to get Verizon (my phones are with Verizon) and I certainly don't understand the SIMS card and having to replace it. Any suggestions on what to purchase would be great apprecited.