As the title says. I know only the concept like : unlock the content by installing app - open it for 30 seconds and it will unlock. So how can it knows that I have run the app for 30 sec? What does it fires back to let the page know a certain action has been done? I tried searching in google but all I got back is WP plugin shit. I want to hire someone for this but I don't even know how to/what to search for basic knowledge.