Alex L

> Hm. I used the word "Service" because I assume EvictionPolicy can be some kind of separate technical business logic that is executing somewhere (_maybe in Android Service =)_) Here...

A side note: I have submitted the article [draft](https://proandroiddev.com/mobile-system-design-exercise-caching-library-8b3b5f1433cd) to ProAndroidDev. It's not perfect but it's _good enough_. We can have more discussions and refine the design later on.

> @weeeBox : how do you restore the last Memory-Cache for the next time of using CachingLibrary? Most likely, you don't want to do anything special since accessing the cached...

Are you referring to a pagination library or something like [RecyclerView](https://developer.android.com/guide/topics/ui/layout/recyclerview)/[UICollectionView](https://developer.apple.com/documentation/uikit/uicollectionview?language=objc)/[UITableView](https://developer.apple.com/documentation/uikit/uitableview?language=objc)?

Honestly, this is the first time I hear about this 🙂 Would you be able to describe the app?

Thanks, @chipbk10! I'm currently on the road - would take a closer look after Christmas.

> Send message use case: (if two users are in a chat session and User A sends a message) The actual implementation depends on the target platform but the idea...

@matzuk, I think it could be too much detail for the interview - it's really hard to explain in such a short time. I would start simple and only add...

@rakeshh91, this WhatsApp screenshot should answer all your questions 🙂 

Hi @elitvynov, would you be able to capture the logcat output?