Any TV you buy will work with any cable or satellite TV service you have. Any PC you buy, even a Mac, will work with any Internet service provider you use. Any landline phone, wired or cordless, will work any phone company's landline service. Duh, duh and duh, right? So can you buy any cellphone you want regardless of who your carrier is? Of course. Unless you live in the United States of America. Why? Because the FCC is a monopoly enabler and can't even follow its own rules.