If you just want to make voice calls with Skype, you're set.

The app is ad-supported, but since it's free, I can live with that.In order to avoid that rigmarole, you can actually use fake credit numbers instead of your own, and you can do that using the site getcreditcardnumbers.com, which can generate up to 9,999 credit card numbers at a time, or just one. This site merely provides the standard 16 digit credit card number that can be used to bypass certain online forms that only ask for the number.