Comparison

DartPDF vs ObsiKO

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

Head to head
About

DartPDF

Edit, annotate, and sign PDF documents directly on your device. This app allows you to fill forms, redact sensitive information, rearrange pages, and even edit text and images within PDFs. All changes are saved locally, ensuring your data remains private.

Highlights
  • Edit text and images
  • Fill forms and add signatures
  • Redact sensitive content
  • Rearrange and export pages
  • OCR scanned PDFs
  • Full-text search
Features
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DartPDF is a PDF editor that runs entirely on your device. Open any PDF to mark it up, fill in forms, sign it, redact content, rearrange pages, or edit the text and images on the page. Changes save back to the original file. Nothing is uploaded. There's no account, no sync, and no ads. Features: • Highlight, underline, strikethrough, and freehand ink • Shapes, arrows, text boxes, notes, and stamps • Edit existing text and add images • Redaction that removes the covered text and images from the file, not just from view • Fill form fields (text, checkboxes, radio buttons, dropdowns), or add your own • Drawn signatures placed anywhere, plus certificate-backed PAdES digital signatures • OCR scanned PDFs so text can be selected and searched • Reorder, delete, and export pages to a new file • Full-text search, text selection, and links • Compare two versions side by side • Open password-protected files Runs on iPhone, iPad, and Mac. Opens PDFs from the Files app, share sheets, or drag-and-drop. Light and dark themes.

About

ObsiKO

Features
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Tired of converting files or picking plugins? Spent the day on settings and never wrote a line? Plenty of features, none of them talking to each other? Everyday writing, LLM wikis, ontologies, Zettelkasten, mindmaps, reading logs, codices, schedules, file conversion — one app, no account or subscription. Obsidian vaults (.md/.canvas/.base) open as-is. (AI runs on your own API key; with Apple Intelligence on, it can run on the device with no key.) ■ You see it first, before anything changes · AI rewrites arrive as a suggestion card — nothing changes until you press Replace · The AI agent works on a copy; only what you pick reaches your notes · Before the first send to an outside AI, it shows what goes where and sends only if you allow ■ Share to the web, sync between devices (GitHub) · "Share to the web" publishes a note at one address — theme, tables and images intact, comments too · The text lives only in your GitHub account, never on our servers; "Stop sharing" takes it down · Sync runs through your own repository and only ever deletes to the trash ■ Write once, it connects itself · A "color" property colors the tab, header, tree icon, .base and codex cards. Define your own types and relations too · Type "book" pops a search that fills the rest; "project" adds start/due to the calendar · Highlight a PDF and quotes collect into a note of the same name, searchable and on the graph · Wiki links, types, relations and PARA form one constellation — more links, brighter star ■ Infinite mindmap canvas (.canvas) · Apple Pencil drawing — turn a sketch into an AI image. Have AI build an editable mindmap, or hand it yours · Auto-build from a note's links, auto-layout, embeds, groups, relations. 5 styles, 10+ presets. Drop a URL or file to add a card ■ .base files and search · Projects, kanban, cards, charts, a library (book/paper search), PARA, a budget that pastes receipts. Dataview queries become tables · Filenames, full text, Korean jamo, semantic search — pin results, bookmark a query, or ask Siri ■ A dashboard and themes you arrange · 50+ widgets plus query and embed boards — calendars, to-dos, habit trackers, stats. 20+ themes, your own fonts ■ Markdown and a writing helper · Calm editing tuned for Korean. Format bar and cheat sheet, Mermaid, 20+ charts, inline drawing, video in a note · 70+ structures across 13 genres (Hero's Journey, Save the Cat, SCQA, character sheets), Socratic questions and style polish · Spell check, dictionaries, device TTS, a saved assistant role, on-device translation ■ Schedules and viewers · A date in any file lands on the calendar (Obsidian Tasks compatible) — year/month/week/day, timeline, widget, reminders · One frontmatter line switches the viewer: book, web novel, messenger, visual novel, codex ■ Clipping and conversion · The article body and photos become a note, not just the URL — share button or RSS · One-click Markdown for doc/docx, PDF, hwp/hwpx — one file or a folder; a read-only panel opens dozens more · Import from Apple Notes, Notion, Evernote, Bear or Logseq — always into a new folder · Highlight PDFs and Markdown to insert or quote. AI OCR and transcription (labelled by speaker) ■ AI agent · Add an API key and go (Claude, Gemini, GPT) — the app is complete without one · Builds mindmaps and .base tables on your phone and reads existing ones. Read-aloud and images in the editor · File creation, automatic memory, LLM wikis, ontology and Zettelkasten design, MCP. Bulk work is desktop-only ■ Export, images, and everything else · Marp properties make a deck. Export to PDF, HWPX, DOCX, EPUB, HTML, ZIP, wiki markup · Dictate on iPhone (on device), Control Center, Lock Screen and Home widgets, Watch quick notes · Ready for iOS 27 — Markdown round-trips with Apple Notes, the new Siri can add to a note, 4×6 widget · Image editing, free image search, colors panel, routines, palette, focus timer, screen lock All of it is free. No account, no payment, a small download.

Screenshots

DartPDF3 screens
ObsiKO4 screens

Verdict

The call

DartPDF and ObsiKO are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

DartPDF ships an update every 4 days, ObsiKO every 6 days. The most recent releases landed on October 13, 2026 and October 10, 2026 respectively.

ScorecardNo meaningful differences
DartPDF versus ObsiKO: the parameters behind the verdict, then further details
ParameterDartPDFObsiKO
PriceFreeFree
Rating5.0 (1 ratings) — better—
Number of ratings1 — better—
Update frequencyEvery 4 days — betterEvery 6 days
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, iPod, MaciPhone, iPad, iPod, Apple Watch
Requires iOS15.0 — better15.1
Further details — not scored
Size53 MB75 MB
Age rating4+4+
DeveloperRailway Engineering Solutions Pty LtdHyojin Kim

In-app purchases

None

DartPDF

No in-app purchases

None

ObsiKO

No in-app purchases

Questions

Is DartPDF free?
DartPDF is free to download, with no in-app purchases.
Is ObsiKO free?
ObsiKO is free to download, with no in-app purchases.
Do DartPDF or ObsiKO have ads?
Neither DartPDF nor ObsiKO shows ads.
Which is updated more often, DartPDF or ObsiKO?
DartPDF ships an update every 4 days, and ObsiKO every 6 days. Most recently, DartPDF was updated on October 13, 2026 and ObsiKO on October 10, 2026.

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