I'm thinking about learn to develop app for iOS. I had a lot of ideas, but most of them I would need the API of that web site. For example: http://www.filmaffinity.com/en/main.html
The point is: is there any other possibility of collect/use information of a site without the API, anything else without the typical parsing or scraping?
To get the most up to date information to your users, you would need to use the API. If you want to store the data locally, you could do some initial scraping and build up your own database and distribute it within your app. This approach is not ideal because your data may become out of date quickly (unless you have a database update mechanism) and the owners of the sites you are scraping may not take too kindly on the matter