Comparison

DEVONthink To Go 4 vs 4DI

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

Head to head
About

DEVONthink To Go 4

Manage your entire knowledge library on your iPad and iPhone. Organize, edit, and annotate documents, notes, and more. Leverage generative AI for summaries, content creation, and advanced search. Syncs privately and securely across devices.

Highlights
  • Document organization and management
  • AI-powered summaries and content creation
  • PDF annotation and editing
  • On-device OCR for searchable documents
  • Cross-device secure synchronization
  • Custom metadata and tagging
  • Shortcuts automation
Features
Read full description

Your entire knowledge library. Always with you. Always private. DEVONthink To Go is your document repository when you're not at your Mac. Collect, organize, edit, and annotate. Use generative AI to work with your stored knowledge or create new documents. Automate with Shortcuts. Our time-tested technology keeps all your data in sync between your Mac, iPad, and iPhone, privately and securely. The professional document and information manager for iPad and iPhone. From DEVONtechnologies, driving innovation since 2002. - Students: Annotate research papers with AI-powered summaries - Teachers: Organize your materials, use AI to create handouts and tests - Researchers: Have your data with you in a robust, powerful knowledge manager - Lawyers: Keep all case files organized and encrypted Have your important documents with you at all times: - Never lose an important document again, keep everything organized - Store PDFs, notes, images, bookmarks, just about any type - File your documents in groups, even more than one group at a time - Use tags, mark documents with flags or as unread, give them a star rating - Versioning lets you return to a previous state of a document - Revision-proof databases prevent edits to documents with special requirements - Sync your data between Macs, iPads, and iPhones, securely and privately Work with your documents: - Edit texts, Markdown files, or rich text documents - Annotate and edit PDFs with common tools - Make scans, scanned PDFs, or images searchable with the built-in, on-device OCR - Add custom, searchable metadata fields to enrich your documents Use generative AI: - Work with your favorite provider and model - Chat with your documents, analyze or summarize them - Transform text or extract text from images and even handwritten notes - Create new images from your data - Find documents using natural language with the AI-powered search assistant - Let the AI make order from chaos, rename documents, add tags, or label or rate them DEVONthink To Go is well-integrated with other apps: - Link to your documents from other apps with universal links - Access all your documents also through the Files app - Clip data from almost any app with the Clip to DEVONthink extension - Use drag-and-drop, inside DEVONthink To Go or between apps - Automate repetitive tasks with Shortcuts actions DEVONthink To Go is great standalone but also works perfectly with DEVONthink for Mac and across multiple devices. Synchronize your databases securely and privately over the local network or through a cloud service of your choice. You decide what data is synced, when, and where. Strong encryption makes sure that your data belongs to you, not to your service provider or us. Privacy policy: https://www.devontechnologies.com/r/privacy End user license agreement: https://www.devontechnologies.com/r/eula

About

4DI

Features
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4DI is an offline reference tool for data integrity in regulated environments — built for QA, validation, manufacturing, and laboratory teams working under GxP. The app organizes data integrity knowledge into five areas: ALCOA++ principles, regulatory frameworks, the data lifecycle, typical inspection findings, and a glossary. ALCOA++ PRINCIPLES 10 principles, each with a clear definition and practical examples contrasting good practice with a typical violation: - Attributable - Legible - Contemporaneous - Original - Accurate - Complete - Consistent - Enduring - Available - Traceable (added per the EMA guideline on computerised systems and electronic data in clinical trials, 2023) REGULATORY FRAMEWORKS 7 frameworks side by side, each with a summary, core requirements, and a link to the official source: - FDA 21 CFR Part 11 - EU GMP Annex 11 - MHRA GxP Data Integrity Guidance - EMA Guideline on computerised systems and electronic data in clinical trials (2023) - PIC/S PI 041 - WHO TRS 1033, Annex 4 — Guideline on data integrity (2021) - ICH Q7 Frameworks are tagged by region (US / EU / International). A comparison view highlights key differences across four topics: audit trail, electronic signatures, risk-based approach, and quality culture & human factors. DATA LIFECYCLE Six phases — Creation, Processing, Review & Approval, Reporting, Retention, Archival & Destruction — each mapped to its relevant ALCOA++ principles, typical pitfalls, and regulatory focus. INSPECTION FINDINGS 17 findings modeled on public patterns from FDA Warning Letters, Form 483 observations, and EU GMP non-conformities. Organized by category and severity, each finding lists the principles violated, its regulatory basis, and remediation measures, with links to official databases. Full search included. GLOSSARY 29 terms — ALCOA terms, regulatory abbreviations (CFR, GMP, GLP, GCP...), technical terms (audit trail, metadata, electronic signature), and quality terms (CAPA, deviation, OOS) — each with a definition and context. Bookmark terms for quick access, get a "term of the day," and search even without typing accents. FIVE LANGUAGES 4DI speaks English, German, French, Spanish and Italian. A new installation starts in your iPhone's language when 4DI supports it. You can switch the language any time in the app's Settings. MADE FOR IPHONE DUO Half open, one half holds the definition or finding you picked while the other lets you browse and compare; fully open, list and details sit side by side like a book. BUILT FOR OFFLINE USE Light, dark, or system appearance. Works entirely offline: no accounts, no tracking, no ads, no permissions required. Bookmarks stay on your device. COMMUNITY & SUPPORT Report a bug, suggest a feature, or flag a content correction through the app's Settings — linked to robspace's public GitHub hub for discussion. For direct support: support@robspace.de. DISCLAIMER: 4DI is a privately developed helping tool. It is not endorsed, certified, or validated by any regulatory authority. Content is for informational purposes only and must not replace official regulatory guidance or professional advice.

Screenshots

DEVONthink To Go 44 screens
4DI4 screens

Verdict

The call

The clearest difference is in-app purchases: 4DI at none against DEVONthink To Go 4's 2. 4DI also leads on update cadence (weekly vs every 3 weeks) and iOS requirement (18.6 vs 26.0). On price, 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. DEVONthink To Go 4 sells 2 in-app purchases, starting at $2.99 per month. 4DI asks for nothing beyond the download.

UpkeepUpdate frequency

DEVONthink To Go 4 ships an update every 3 weeks, 4DI weekly. The most recent releases landed on October 27, 2026 and October 25, 2026 respectively.

Scorecard3 real differences · 7 level
DEVONthink To Go 4 versus 4DI: the parameters behind the verdict, then further details
ParameterDEVONthink To Go 44DI
PriceFreeFree
Rating4.7 (258 ratings) — better—
Positive reviews44.8% of reviews—
Number of ratings258 — better—
Update frequencyEvery 3 weeksWeekly — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad — betteriPhone
Requires iOS26.018.6 — better
Further details — not scored
Size193 MB5 MB
Age rating17+4+
DeveloperDEVONtechnologies, LLCRobert Poetzsch

In-app purchases

2 purchases

DEVONthink To Go 4

Subscriptions2
  • Monthly1 Month trial$2.991 Month
  • Yearly1 Month trial$19.991 Year
None

4DI

No in-app purchases

Questions

Is DEVONthink To Go 4 free?
DEVONthink To Go 4 is free to download, with in-app purchases available.
Is 4DI free?
4DI is free to download, with no in-app purchases.
Do DEVONthink To Go 4 or 4DI have ads?
Neither DEVONthink To Go 4 nor 4DI shows ads.
Which is updated more often, DEVONthink To Go 4 or 4DI?
DEVONthink To Go 4 ships an update every 3 weeks, and 4DI weekly. Most recently, DEVONthink To Go 4 was updated on October 27, 2026 and 4DI on October 25, 2026.

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