What is the best app to buy USDT in Australia?

Could you please elaborate on what application would be most suitable for purchasing USDT in Australia? I'm interested in understanding the criteria you consider when evaluating these platforms, such as ease of use, transaction fees, security measures, and the availability of other cryptocurrencies. Additionally, I'd like to know if there are any specific features or services that these apps offer that make them stand out from the competition. Your insights would greatly assist me in making an informed decision about which app to choose for my cryptocurrency purchases in Australia.