I recently ordered a straight talk iPhone 5s from swappa. I plan to just use it as a wifi device but my question is, can I use any sim card for the initial set up or does it have to be specifically straight talk sim. Also does the sim have to be activated and working?? And after the initial set up and activation can I simply remove the sim card and the phone still work as a wifi device? Sorry this is my first time buying a phone.
Yes, there is a SIM card required to activate your iPhone. After activation you can use your iPhone without any SIM card (except some features off course). You could use a SIM card from your current phone, provided that it is a nano-SIM (i.e. the iPhone 5s SIM slot supports nano-SIMs).