Australia’s main telecommunications companies (although Telstra has by far the largest network in the NT):
Telstra (www.telstra.com.au) The main player − landline and mobile phone services.
Optus (www.optus.com.au) Mobile network covers Darwin, Jabiru, Nhulunbuy Katherine, Tennant Creek, Alice Springs, Yulara and a few spots along the Stuart Hwy.
Vodafone (www.vodafone.com.au) Coverage only in Darwin, Jabiru, Katherine, Alice Springs and Yulara.
European phones work on Australia's network, but not most American or Japanese phones. Use global roaming or a local SIM card and prepay account.
Numbers Australian mobile-phone numbers have the prefix 04xx.
Reception Australia's mobile networks service more than 90% of the population but leave vast tracts of the country uncovered. Darwin and most of the NT's settled areas get good reception, but as the towns thin out, so does the service. Don't rely on coverage in outback areas, except in Yulara.
Networks Australia's digital network is compatible with GSM 900 and 1800 (used in Europe), but isn't compatible with the systems used in the USA or Japan.
Providers It's easy and cheap to get connected short term – the main service providers all have prepaid mobile systems.
A range of phonecards ($10, $20, $30 etc) is available from newsagencies and post offices. Phonecards can be used with any public or private phone by dialling a toll-free access number and then the PIN on the card. Rates vary from company to company – shop around.
The only phone boxes you're likely to see are in remote towns and roadhouses where there's no mobile coverage.