I have a 3GS that I'll be upgrading to an iPhone 4 at launch. Right now, my wife just has a non-smartphone but would like to upgrade hers to an iPhone 4 as well. So here are my questions: 1) If she gets an iPhone 4, she *has* to choose one of the data plans, right? Specifically, you can't get an iPhone without a data plan, right? She really has no need to use data when she's on the go, but would like to use it on WIFI. 2) Assuming she chooses the cheapest 200MB data plan for $15/mo, could she then go into her iPhone settings and turn off Cellular Data to prevent from going over the 200MB by accident? She is not tech-savy and would have no idea how much data she is using. I'm thinking of getting her the 200 MB plan and then just turning off cellular data when and if she gets close to going over (assuming she'll get a text when she is close). I know the option is there on the iPhone, but not sure how it works. Will she still be able to get voicemails (assuming this uses data to retrieve Visual Voicemail)? 3) I am planning on sticking with the Unlimited Data plan on MY iPhone 4. Signing her up for the 200MB plan will not affect MY unlimited plan, will it? Thanks!