Nell: Designing prompt-to-podcast from zero to private beta

Show Creation

Nell turns any prompt, topic, article or question into a 5-10 minute podcast episode. I designed the mobile product end to end, working with the cofounder of SoundCloud, engineers and the head of content. The idea comes from the adaptive Primer in Neal Stephenson's The Diamond Age: curiosity in, personalized learning out.

Problem: AI can write the script, but making a podcast is still work

ChatGPT, Claude and NotebookLM can already summarize and explain. Turning that into something polished enough to listen to still takes too much effort. Nell had to feel native to audio, not like a chatbot with an export button.

What I owned

  • Information architecture: Home, show and episode structure
  • Creation: The show creation and generation flow
  • Core flows: Host picker, search, profile and onboarding
  • Prototyping: High-fidelity Xcode prototypes for testing mobile interactions

Key decisions

  • Public by default: Shows start public to increase discovery and engagement
  • Designing the wait: Skeletons, spinners and shimmering text for long-running AI generation
  • Identity: How usernames, full names and creator profiles work together
  • Measurement: Onboarding and retention metrics defined in PostHog

Outcome: Private beta, backed by top investors

  • Investors: Danny Rimer (Index Ventures), Guillermo Rauch (Vercel), Anton Osika (Lovable), Mati Staniszewski (ElevenLabs) and Soleio
  • Status: In private beta as of August 2026

Selected Screens

Home screen

Continue listening at the top, then episodes and shows picked for you.

Show and Episode Details

Library

Created shows, episodes, follows, saves and downloads in one filterable view. A lock marks private shows.

Nell library detail
Nell library detail

Selections from the Design System

Nell design system

Product Analytics

A tracking plan from onboarding through generation, listening and retention, built to answer five questions, including how long it takes to reach a first podcast.

Nell product analytics
Nell product analytics

Appendix

Recent list items
Recent episodes
Rules on pretty printing elapsed time
Nell appendix

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Nell case study

AI-generated from Dennis's voice