I'm considering upgrading my phone from the one I have now (LG Trax) to something a little more 'high tech'. I'm sort of going back and forth from Samsung Jack and LG Xenon. I have to stick with AT&T.

Would I have to upgrade my current plan for my flip phone to use either one? I'm trying to keep things pretty cheap, so I don't want any expensive internet charges or anything. Pretty much all I do is call and text.
Also, are there extra charges for using the GPS on the Jack? I'd kind of prefer the Jack to the Xenon, but I'd like opinions as well.


Thanks!