The Australian dollar is a stable currency. ATMs are widely available. Credit cards are accepted in most hotels and restaurants.
Tipping isn't obligatory in Australia and tips are completely optional, as it's presumed that staff will be paid appropriately by their employers.
Restaurants It's common to tip to 10%, but only if you're completely happy with the service.
Cafes Not necessary, but sometimes there's a tip jar on the counter.
Hotels Some people tip their porter, but it's not expected.
Taxis Round up to the nearest dollar.