Australian App Patents Research Paper

I want a research paper outlining the entire process and costs associated with patenting a mobile application in Australia across all platforms (Android, Apple etc). Do you have to create the app first or can it be an idea? Is there a way to search app patents to see if something is already patented? How much does such a patent cost in Australia? In other markets? Or globally? Then I want research on the best app developers available on Freelancer for apps in the advertising and rewards-for-spending areas. Thank you