Apparently there are international flights between Davao International and some cities in Australia like Perth, Melbourne and Brisbane.
Source: https://www.skyscanner.com.ph/routes/dvo/au/davao-international-to-australia.html
Davao City is the gateway to the unspoiled beaches of Southern Mindanao like Samal Island, Davao del Norte and surfing city Mati, Davao Oriental. Also up and coming white beach destination Baganga, Davao Oriental (https://www.google.com/search?client=firefox-b-e&q=baganga+davao+oriental).