In which situations is it recommended to delete or update cached data?

It is recommended to delete or update cached data in the following situations:

• Data is outdated or has changed: when the source data on the server or in the source has been updated, the cache should be refreshed to avoid showing old information to the user.
• Cache expiration (TTL): if a time-to-live is set for the cache, data is automatically deleted or updated after it expires.
• Insufficient memory: when device resources are limited, clearing the cache can free up space.
• Cache errors or corruption: if cached data is corrupted or causes errors, it should be removed.

In iOS, cache management often involves classes like URLCache or custom mechanisms. For example, when new data is received from the server, the cache can be updated:

let urlCache = URLCache.shared
urlCache.removeAllCachedResponses() // clear all cache
// or update specific cache

Proper cache management helps maintain data relevance and optimize resource usage.