The iPhone 4 is officially launching in the US territory of Guam on Friday. The expansion follows a series of recent releases, including South Africa and South Korea. GTA TeleGuam is set to be the carrier, and has already announced plan details. Of special interest may be the day-one availability of tethering, with a monthly cost of $15. It can be added and removed as needed. GTA is selling two family plans, and three standard plans.
