application cache

Good morning, Currently I am developing an ios application and I would like some help to be able to save the data in the application cache, because I currently find nothing on this subject and yet I spent a day doing research without the slightest response, Enzo.

Hello In my application, i want to know my application's cache size and data size when i start the application, and also if it is large then i want to delete them. How can i do this?