After trying Redux pattern in Codeforces Watcher with Contests feature, we couldn't stop and, as a result, migrated all the application to this next-gen pattern. Update is already available in Google Play. We've already noticed decreased number of NPEs, better app stability and better app UX. Don't believe us? Just try it by yourself!
For those who are interested, here is a full series of articles:
Redux for Android with Kotlin in practice, Part 1: Initial setup
Redux for Android with Kotlin in practice, Part 2: Fetching data from network
Redux for Android with Kotlin in practice, Part 3: Final touches
As always thanks to BOGDAN_ for implementing the migration and to alla_dubovska for writing these articles.