Comparison

Sigma Domain vs Chatmark

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

Head to head
About

Sigma Domain

Features
Read full description

Sigma Domain is the AI workspace where you bring the tools โ€” and the AI does the work. The conversation is powered by Claude, the model family behind the world's best coding and agent systems. When you want a sanity check, tap the brain button and get a second opinion from a catalog of 70+ leading models โ€” OpenAI, Meta, Mistral, DeepSeek, Amazon, and more โ€” with a summary of where they agree or differ. YOUR AI TOUR GUIDE Going somewhere? Start a tour and Sigma Domain narrates the places you pass โ€” the history, the architecture, the stories โ€” spoken aloud while you drive or walk. Road trips, neighborhood walks, museum visits: it's like a private radio station about wherever you are. POST YOUR OWN TOOLS Most AI apps are just chat. Sigma Domain includes a marketplace of thousands of ready-to-use tools โ€” and you can register your own functions, APIs, and integrations, public or private. Your tools become part of the AI's toolkit, callable in plain English by you, your team, or anyone you share them with. LIVE MAPS YOU BUILD TOGETHER Search properties and places, pin and compare them on a shared map, vote with your team, and generate reports โ€” commute times included. SKILLS Expert playbooks the AI loads on demand: create and edit Word documents, PowerPoint decks, Excel spreadsheets, PDFs, and more โ€” so answers become finished documents, not just text. AI JOBS Hand off multi-step work. The AI plans the steps, calls the right tools, and reports back when it's done. WHY SIGMA DOMAIN - Powered by Claude for the main conversation โ€” the engine behind today's best AI agents - Second opinions from 70+ models with one tap - A tool marketplace you can add to โ€” publish your own tools in minutes - GPS-aware audio tours, live shared maps, document skills, and automated jobs - Natural conversation โ€” no prompt engineering required Bring your tools. Ask for outcomes. Sigma Domain does the rest. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Chatmark

Features
Read full description

Chatmark gives you a simple way to: - Organize conversations from multiple AI apps Key Features - Save chats from AI apps instantly via Share Sheet - Import ChatGPT shared links with structured parsing - Clean, readable conversations (user / AI separation) - Markdown support for better readability - Local storage (your data stays on your device) Privacy First - Chatmark stores everything locally on your device. No accounts. No cloud. No tracking.

Screenshots

Sigma Domain4 screens
Chatmark4 screens

Verdict

The call

The clearest difference is in-app purchases: Chatmark at none against Sigma Domain's 2. Sigma Domain's advantage is update cadence (every 2 days vs every 6 weeks). On price, ads, device support and iOS requirement there is nothing between them.

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

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. Sigma Domain sells 2 in-app purchases, starting at $5.99 per month. Chatmark asks for nothing beyond the download.

UpkeepUpdate frequency

Sigma Domain ships an update every 2 days, Chatmark every 6 weeks. The most recent releases landed on October 28, 2026 and October 18, 2026 respectively.

Scorecard2 real differences ยท 4 level
Sigma Domain versus Chatmark: the parameters behind the verdict, then further details
ParameterSigma DomainChatmark
PriceFreeFree
Update frequencyEvery 2 days โ€” betterEvery 6 weeks
AdsNoNo
In-app purchasesYesNo โ€” better
DevicesiPhone, iPadiPhone, iPod
Requires iOS16.616 โ€” better
Further details โ€” not scored
Size73 MB27 MB
Age rating4+4+
DeveloperSigma DomainTaeeun Kim

In-app purchases

2 purchases

Sigma Domain

Subscriptions1
  • Standard Monthly Sigma Domain$5.991 Month
One-time1
  • Additional Usage - Sigma Domain$9.99
None

Chatmark

No in-app purchases

Questions

Is Sigma Domain free?
Sigma Domain is free to download, with in-app purchases available.
Is Chatmark free?
Chatmark is free to download, with no in-app purchases.
Do Sigma Domain or Chatmark have ads?
Neither Sigma Domain nor Chatmark shows ads.
Which is updated more often, Sigma Domain or Chatmark?
Sigma Domain ships an update every 2 days, and Chatmark every 6 weeks. Most recently, Sigma Domain was updated on October 28, 2026 and Chatmark on October 18, 2026.

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