Selling 3GS and 4S

[marysville]

I have a 3gs and will soon have a 4s for sale.
How can I clean them up, i.e., leave nothing of mine on the phones prior to selling or passing them on?

 

[cyks]

Connect to iTunes, restore as new.

 

[marysville]

Connect to iTunes, restore as new.

I take it this process will not affect my current, still in use, iPhone?

 

[PsstGreek]

I take it this process will not affect my current, still in use, iPhone?

Nope.

 

[marysville]

Nope.

And thanks so much for your help. Michael