I now have an iPhone 4 and am getting ready to sell my 3Gs. However, a family member would love to have the 3Gs but does not use texting, email, etc. Is there a way I can use the 3Gs on our ATT Family plan but without the cost of a data plan? My new iPhone 4 is on the Family Plan. Is this where "unlocking" the iPhone would apply? Very basic question - easier (for me) to ask than searching.