How is caching done in applications like Instagram?

Question

Android

Judging by the decrease in available space, the photos are definitely cached there)
Are announcements of posts from the feed, detailed descriptions and comments cached in the local database - after all, they are constantly changing? Few of them are reopened, only if they are not added to favorites.

Answer 1

There are special libs that can properly cache photos. Glide, Picasso, for example. The rest of the data, in my opinion, is not cached. But putting them in the local database is not a problem.