JT is heading to Australia for a week. What mobile service should he use? Leo says that Google Fi and T-Mobile both work all over the world. The services isn't as fast, but it's free Edge service, which is nice. He can then use local Wi-Fi at the hotel, coffee shops, etc. whenever he can. The Global plan on T-Mobile is $20 a month, but it's only slightly faster, and the speeds vary wildly. He could also buy a "day pass" of 4G access.
Here's a Reddit thread on using Google Fi in Australia. JT should understand though, that with Google Fi, he would need an approved phone. And if he has a Pixel phone, he should be on Fi anyway.