Most avid users of mobile telephony services can today access different alternatives to minimize the cost of telephone calls. Cards, for example, are a very efficient option to control consumption. Some companies let you know online called history, detail of consumption as well as other management operations that allow you to better control the use of your line. How do prepaid cards work? In General, all work the same, after acquiring it, you receive a PIN. Before making a call, you should only dial the access number, enter the PIN and number as the last step, the number of the person with whom you want to communicate. What is the cost of the cards? There are cards of between 6 and 12 euros, depending on the characteristics of the benefit (free talk minutes, etc). Some companies are also offering fixed payment plans that are very interesting to those who tend to make frequent calls to outside the country. One of the most interesting features in this case, is that contacts can communicate, paying only as if it were a local call. -Attention: Before purchasing a card, advise for the conditions of the company that sells them, making sure it does not steal minutes and that of course there are no additional charges.