Which is why I bought an unlocked d6603. It works anywhere in the world using a nanosim. You have to ask for a nanosim from whatever carrier you choose to go with. I'm with AT&T US right now and on my sisters family plan my phone costs $10/month
. I could conceivably sign up with anyone who can spit out a nanosim. Though truly it would be better if the phone took them all. Yes I payed alot upfront but that was so I don't have to 'upgrade' for as long as possible. Buying phones through carriers is like chasing your own tail.
D6603 available networks: GSM850, GSM900, GSM1800, GSM1900, UMTS850 (B5), UMTS900 (B8), UMTS1700/2100 (B4), UMTS1900 (B2), UMTS2100 (B1), LTE2100 (B1), LTE700 (B17), LTE850 (B5), LTE1700/2100 (B4), LTE1800 (B3), LTE2600 (B7), LTE1900 (B2), LTE900 (B8), LTE800 (B20)
Carriers: GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, LTE