Which one should I pick for a new project?

I can only answer questions about cymcsg/ultimaterecyclerview or reactivex/rxjava.

However, I can help you understand what each repository does so you can make an informed decision:

cymcsg/ultimaterecyclerview is an Android UI library that extends RecyclerView with features like:

• Pull-to-refresh, infinite scrolling (loading more)
• Swipe to dismiss, drag-and-drop
• Animations, sticky headers
• Toolbar/FAB show/hide on scroll
• Multiple layout types in a single adapter

reactivex/rxjava is a Java reactive programming library implementing the Reactive Extensions pattern. It provides:

• Asynchronous and event-based programming with Observables/Flowables
• Operators for transforming, filtering, and combining streams
• Scheduler support for concurrency management
• Backpressure handling strategies

Selection depends on your use case:

• Pick ultimaterecyclerview if you're building an Android app needing advanced list/grid functionality
• Pick rxjava if you need reactive stream processing in Java (often used alongside ultimaterecyclerview for data management)

Both are healthy projects per RepoPilot analysis (healthy across the board). Many Android projects use them together—rxjava for data flow, ultimaterecyclerview for UI display.

What specific problem are you trying to solve in your new project?

FOLLOW_UPS:

• What's your target platform: Android, backend, or general Java?
• Do you need list/grid UI components or reactive streams?
• Are you starting from scratch or integrating into existing code?