Zo vs Readwise Reader
Readwise Reader is one of the most powerful read-it-later apps available. Built by the team behind Readwise (the highlight sync service), it's designed for serious readers who want to retain what they read. It handles articles, PDFs, newsletters, Twitter threads, and even YouTube transcripts.
But like every read-it-later service, your content ultimately lives in someone else's system.
The Pocket Lesson
Mozilla's Pocket operated for 18 years before shutting down on July 8, 2025. Users had until October 8 to export before all data was permanently deleted.
Readwise Reader isn't Pocket. It's a well-funded, actively developed product. But the lesson remains: any service can change or shut down. Your reading archive shouldn't depend on any company's continued operation.
What Readwise Reader Does Well
Readwise Reader is genuinely excellent at what it does:
Unified content: Articles, PDFs, newsletters, Twitter threads, YouTube transcripts
Advanced highlighting: Multiple colors, notes, image/table annotations
Ghostreader AI: Ask questions, define terms, simplify text
Highlight sync: Seamless connection to the Readwise spaced repetition system
Integrations: Exports to Notion, Obsidian, Roam Research
Offline access: Read without internet
Import from everywhere: Pocket, Instapaper, Kindle highlights
For researchers and serious readers who want to retain information, Reader is excellent.
The Underlying Problem
According to a 2024 Pew Research study, 25% of web pages that existed between 2013 and 2023 are now gone. 66.5% of links over a nine-year period were dead.
Readwise Reader caches content and syncs highlights beautifully. But:
The content lives on Readwise's servers
You're saving highlights, not the source material
If the original disappears and Readwise changes, your archive is at risk
Your knowledge base depends on continued subscription
We wrote about this: How to save a webpage forever.
How Zo Approaches This Differently
When you save an article on Zo:
Zo fetches the page
Extracts the content
Converts to clean markdown
Saves it as a file on your server
The article exists as a file you own. Not cached in a service – saved as an actual file. You can read it, search it, ask AI about it, and it will still be there in 20 years.
What About Spaced Repetition?
Readwise's killer feature is spaced repetition for your highlights. Review what you've read at optimal intervals to commit it to long-term memory.
Zo has an answer: set up a plain-text flashcard system using hashcards.
Hashcards stores your flashcards as markdown files – the same philosophy as Zo. Your cards are just text files you can edit with any editor, sync with Git, and own forever. It uses FSRS (Free Spaced Repetition Scheduler), the same modern algorithm now available in Anki.
The difference: your flashcards are files you control, not entries in someone else's database. And you can use AI to generate cards from your saved articles.
Feature Comparison
Save articles
Readwise: Yes (cached)
Zo: Yes (as files you own)
PDF support
Readwise: Excellent
Zo: Yes
YouTube transcripts
Readwise: Yes
Zo: Yes (auto-extract)
Highlighting
Readwise: Excellent (multi-color, annotations)
Zo: Via notes and AI
Spaced repetition
Readwise: Yes (core feature)
Zo: Yes (via hashcards)
AI features
Readwise: Ghostreader
Zo: Full AI (multiple models, code execution)
Data format
Readwise: Proprietary database
Zo: Markdown files
Export
Readwise: To note apps
Zo: Already files – just download
Automation
Readwise: Limited
Zo: Yes (agents)
Beyond reading
Readwise: No
Zo: Full computer (code, automation, hosting)
Different Philosophies
Readwise Reader is built around the idea that you should highlight and review to retain knowledge. It's excellent for that workflow – polished apps, seamless sync, great UX.
Zo is built around the idea that you should own your files and have AI help you work with them. Your articles are markdown files. Your flashcards are markdown files. Everything is portable, version-controllable, and yours forever.
If you want the most polished reading and review experience out of the box, Readwise is hard to beat.
If you want to own your content as files, build your own workflows, and have full control, Zo is the better fit.
Beyond Reading
The bigger difference: Zo is a computer, not just a reading app.
With your saved articles on Zo, you can:
Ask questions: "Summarize everything I've saved about productivity"
Build automations: Auto-save from newsletters, RSS, specific topics
Generate flashcards: Ask AI to create spaced repetition cards from your articles
Create tools: Build custom apps to explore your archive
Run code: Process, analyze, transform your content
Your archive becomes infrastructure, not just a reading list.
Other Alternatives
Evaluating options after Pocket's shutdown? Here are other read-it-later apps:
Matter: Modern reading app with AI features ($8/month)
Instapaper: Classic, clean reading interface
Raindrop.io: Bookmark manager with reading mode ($33/year)
Wallabag: Open-source, self-hosted (€11/year hosted)
Plinky: Apple-focused link saver ($3.99/month)
Pricing
Readwise (includes Reader):
Monthly: $12.99/month
Annual: $9.99/month (billed yearly)
50% student discount available
Zo:
Plans start at $18/month
Includes AI, storage (100GB), automation, and everything else
Get Started
Ready to own your reading archive as files? Try Zo Computer and save content you control forever.