Comparison

Obsidian vs ReadOS

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Obsidian

Organize your thoughts and ideas with a powerful knowledge base that stores your notes as plain text Markdown files. Access your personal second brain on any device, with extensive customization options and community-driven plugins.

Highlights
  • Local Markdown file storage
  • Customizable toolbar
  • Graph view
  • Community plugins
  • Themes
  • Sidebar pinning
  • iCloud vaults
Features
Read full description

Obsidian is a powerful knowledge base that works on top of a local folder of plain text Markdown files. It is a second brain, for you, forever. Now available on the go for iOS! Features include: - Customizable toolbar - Pull down quick actions - Graph view - Community plugins - Themes - Sidebar pinning for tablet - iCloud vaults

About

ReadOS

This app is an AI-powered workspace for iPad that helps you read, research, and create. It connects your source materials and project context, allowing you to move seamlessly from understanding to creation. Features include AI summarization, knowledge mapping, and document analysis.

Highlights
  • AI-powered research agent
  • Contextual reading and note-taking
  • Knowledge mapping and visualization
  • Document, spreadsheet, and presentation creation
  • Web browsing and data analysis
  • Audio and video transcription
  • Multi-step task automation
Features
Read full description

ReadOS is an all-in-one, desktop-class AI agent workspace for iPad, built around the place serious work often begins: reading. Open a PDF, collect research, inspect evidence, create a report, analyze data, build office files, and continue the task without rebuilding context across separate apps. ReadOS keeps source materials, reading position, selections, files, and project context connected so you can move from understanding to creating. READ WITH CONTEXT • Open PDFs, EPUBs, Markdown, images, local audio and video files, and common office files. • Navigate document structure and page references when the source provides them. • Annotate PDFs, take notes, organize tabs, and export annotated documents. • Build knowledge maps and visual explanations connected to source material. RESEARCH WITH READEX Readex is the AI agent inside ReadOS. When you choose to share content with it, Readex can work with the current document, selected passages, attachments, webpage context, and files in your workspace. Use Readex to: • Summarize and compare source material. • Develop study guides, research plans, and structured notes. • Trace an answer back to relevant pages and context. • Work across multiple files while keeping the research question visible. CREATE, AUTOMATE, AND DELIVER With ReadOS Pro, Readex can help: • Create and edit documents, spreadsheets, and presentations. • Analyze data with Python and JavaScript. • Build charts, tables, interactive visualizations, and knowledge maps. • Browse the web, inspect pages, collect relevant context, and carry out browser tasks. • Transcribe and analyze local audio and video files, extract useful frames, and continue from a playback position. • Carry out multi-step and long-running tasks across available files and tools, with progress you can review and stop. FREE AND PRO ReadOS Free includes library management, local file opening and playback, PDF annotation, notes, navigation, tabs, workspaces, and annotated-PDF export. ReadOS Pro unlocks Readex and advanced AI-assisted work, including browser automation, creation and editing tools, code and data analysis, document and media understanding, and multi-step or long-running tasks. ReadOS Pro is available through Apple In-App Purchase as an auto-renewing annual subscription or a one-time lifetime purchase. ReadOS Pro also requires a supported AI provider account or compatible API connection. Provider subscriptions, usage quotas, and model or API fees are separate and are not included with ReadOS Pro. Availability and results can vary by source format, selected provider or model, network access, and permissions. Start with what you are reading. Keep the context. Build what comes next. TERMS OF USE ReadOS uses Apple's Standard Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Obsidian4 screens
ReadOS3 screens

Verdict

The call

The clearest difference is review sentiment: ReadOS at 100% against Obsidian's 62%. ReadOS also leads on rating (5.0 vs 4.5). Obsidian's advantage is in-app purchases (none vs 2) and ratings volume (2.8K vs 8). On price, update cadence, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. ReadOS sells 2 in-app purchases, starting at $19.99 per year. Obsidian asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

ReadOS holds the better App Store score, 5.0 against 4.5. That said, the two scores are not equally well evidenced: Obsidian has 2.8K ratings behind it against 8, so its average is the more settled of the two. Written reviews point the same way: 62% of Obsidian's written reviews are positive against 100% of ReadOS's.

UpkeepUpdate frequency

Obsidian ships an update every 3 weeks, ReadOS monthly. The most recent releases landed on November 12, 2026 and October 31, 2026 respectively.

Scorecard7 real differences · 4 level
Obsidian versus ReadOS: the parameters behind the verdict, then further details
ParameterObsidianReadOS
PriceFreeFree
Rating4.5 (2.8K ratings)5.0 (8 ratings) — better
Positive reviews62.0% of reviews100.0% of reviews — better
Number of ratings2.8K — better8
Update frequencyEvery 3 weeks — betterMonthly
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFreemium
Best chart rank#118 — better—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better26.0
Further details — not scored
Size39 MB993 MB
Age rating4+17+
DeveloperDynalist Inc.秀芳 王

Customer experience

Obsidian

All ratings2,803 ratings
Positive85.4%
Neutral4.0%
Negative10.6%
Written reviews1,354 reviews
Positive62.0%
Neutral12.0%
Negative26.0%

ReadOS

All ratings8 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews6 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Obsidian

Reported bugs

3 issues
  • Sync issues leading to data loss
  • Freezing and crashing on mobile devices
  • Editing bugs and text input issues

Requested features

5 requests
  • Improved sorting and organization options
  • WYSIWYG editing on mobile
  • Better integration with other cloud storage services
  • More intuitive onboarding process for new users
  • Native mobile widgets and share sheet integration

ReadOS

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Obsidian

No in-app purchases

2 purchases

ReadOS

Subscriptions1
  • ReadOS Pro Annual7 Days trial$19.991 Year
One-time1
  • ReadOS Pro Lifetime$69.99

Questions

Is Obsidian free?
Obsidian is free to download, with no in-app purchases.
Is ReadOS free?
ReadOS is free to download, with in-app purchases available.
Which has better reviews, Obsidian or ReadOS?
ReadOS is rated higher. Obsidian averages 4.5 out of 5 from 2.8K ratings, while ReadOS averages 5.0 from 8 ratings.
Do Obsidian or ReadOS have ads?
Neither Obsidian nor ReadOS shows ads.
Which is updated more often, Obsidian or ReadOS?
Obsidian ships an update every 3 weeks, and ReadOS monthly. Most recently, Obsidian was updated on November 12, 2026 and ReadOS on October 31, 2026.

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