Just for my curiosity, what are processes happening,when I press buy button in software center ? . I just noticed that it updates software cache when I pressed buy button. It means it adds a temporary repository for that app?
1Source:Ubuntu Software Center Documentation
If the App is free, but shows the buy button and $0.00 like the app in the image below, after you login, you will get
And below is the final outcome. The App was installed without paying a dime.
For repositories, and how they integrate with USC seeIntegration with Ubuntu Software Center.