We're an Australian business, so everything is priced and charged in AUD. There are no hidden fees, no currency conversion surprises, and no add-ons at checkout. The price on the plan page is the price you pay.
Since Roamly charges in AUD and is an Australian business, your Australian bank should not apply any foreign transaction fees. If you're using a card issued outside of Australia, your bank may apply a currency conversion fee — check with your card issuer.