RoamTheWorldCellPhones.com

Cellphone GSM Frequencies: 850/1900

(This means you will need a GSM cellphone that will work on 850MHz or 1900Mhz to use it in Hawaii.)

Cellular carriers for Hawaii

AT&T Mobility

Frequency: GSM 850/1900
Website: www.wireless.att.com

Coverage Map

T-Mobile USA

Frequency: GSM 1900
Website: www.t-mobile.com

Coverage Map (Select HI from State in the top right of the window)

If you've used either of these networks or roamed in Hawaii, please post about your experience and the cost. Feel free to ask questions.