Need cash when I land, best place in Kiribati? Airport or places in the city?
The airport exchange is the worst option. You'll get a much better rate at the ANZ Bank in the city. There are ATMs at the ANZ branches in Betio, Bairiki, and Bikenibeu, as well as one at Tungaru Central Hospital. The country runs on Australian dollars, so if you already have some, you might not even need to exchange. Otherwise, just head to a bank branch for a better deal.
Don't use the airport exchange, it's a complete rip-off. The best way to get cash is to go to the ANZ Bank in South Tarawa. They have an ATM and they can also do exchanges at the counter. The currency is the Australian dollar, so if you have it, you're all set. If not, you'll need to use your debit card at the ATM. It's a much better rate than you'll find at the airport.
I can tell you from my trip that you won't want to use the airport exchange. The best and only reliable way to get cash is from the one ATM at the ANZ Bank in South Tarawa. You should also bring a good supply of Australian dollars in cash with you, just in case the ATM is not working. The entire country is a cash-based economy, so you'll need it for everything from taxis to food.
The airport exchange is a terrible option. The best way to get cash is from an ATM at the ANZ Bank. There is only one ATM on the main island of South Tarawa, so you should plan accordingly. The currency is the Australian dollar, so it's easy to deal with if you have that currency. But if not, you'll need to use the ATM or a money transfer service like Western Union. Just be aware that ATMs can sometimes be out of order.