OK. Apologies in advance if this is a dumb question. I'm thinking about getting rid of my phone service on my iPhone 4 (too expensive, don't use it that much, can get data with my iPad Mini that is cheaper). Anyhow, if I disconnect the service, what should I expect to happen with my phone? Will I still be able to use GPS for apps like Runkeeper? Will it be functionally identical to an iPod Touch? Any things I'm not considering? Thanks.