I want an new iPhone from this iPhone 4 I got now. I like the way the iPhone 5S looks. It has the true iPhone style I like. But I want a bigger screen like the iPhone 6. Do the iPhone 5S come with a sim card slot? And do I have to get a service plan with the easy pay plan? I don't want to spend $70 or more a month for the iPhone 6 or iPhone 5S. I'm on straight talk with my iPhone 4 and I'm locked to AT&T. Do I have to unlock the iPhone 5S for straight talk? I don't know if I have to unlock because it said I don't have to unlock but my cousin keep saying you have to unlock now. And if I have to get a service plan, do it have to be unlimited?
I know there's a lot of questions but I wanted to be detailed and wanted everything I'm wondering about answered. Please answer with detail.
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