Here are the Websites where I got the information about the Disadvantages and Advantages.

www.bizhelp24.com/it/mobile-phones-in-business is where I got my information from about the Advantages. I couldn’t find any other Website for Advantages of Mobile Phones.

www.bizhelp24.com/it/mobile-phones-in-business is where I got some of my information from about Disadvantages. 

www.britishcouncil.it/students/rome/mobphones.htm is where I got some more information from about Disadvantages.

www.ezinearticles.com/?Advantages-and-Disadvantages-of-Prepaid-Cell-Phones is where I got the rest of my information from about Disadvantages

I also got some information leaflets from The Carphone Warehouse.