Does anyone know anything about using these. I'll be in the U.K. for about 3 weeks and wondered about using one to call home. Can you use them with your cellphone? Are there ones to stay away from? I've never used a calling card before and wanted to find the least expensive way to call back home while I'm gone. Thanks for your help.

 

Buy a cheap cell and a calling card with local UK access numbers (probably easier to get such a card in the UK than in the US).
The calling cards use local numbers to access low-cost international lines-- if you are in FL, you would call a local Miami, Clearwater, Jacksonville, etc. number on the calling card to access its lines first, then dial the international number out. If you are in England, you don't want to use a calling card with a US number.

Also, as I understand it, most people will be billed up the wazoo by their cell carrier for international use if they use a US phone abroad.