Comparison

Sigma Domain vs Thinkdo AI

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

Thinkdo AI

Features
Read full description

Thinkdo AI is the world's simplest and most powerful place to capture your ideas and research them on the go. Powered by frontier AI models like Claude, OpenAI, Perplexity. AI powered organisation: Just type in or speak an idea & Thinkdo AI automatically organises it as a new idea thread or in an existing idea thread. AI powered research: With one tap, research with AI on any idea thread, with all the idea notes captured. SUBSCRIPTION OPTIONS: Thinkdo AI offers optional premium subscriptions: - Beginner ($4.99/month): 700 captures, 70 research queries - Pro ($9.99/month): 1,400 captures, 140 research queries - Pro Max ($24.99/month): 2,800 captures, 280 research queries Payment will be charged to your Apple ID account. Subscriptions automatically renew unless cancelled at least 24 hours before the end of the current period. Manage subscriptions in Settings > Apple ID > Subscriptions. Terms of Use: https://thinkdoai.xyz/terms Privacy Policy: https://thinkdoai.xyz/privacy

Screenshots

Sigma Domain4 screens
Thinkdo AI4 screens

Verdict

The call

Sigma Domain and Thinkdo AI are too close to call on the numbers: across 5 compared parameters โ€” price, ads, in-app purchases and device support among them โ€” neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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 and Thinkdo AI sells 3 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

ScorecardNo meaningful differences
Sigma Domain versus Thinkdo AI: the parameters behind the verdict, then further details
ParameterSigma DomainThinkdo AI
PriceFreeFree
Update frequencyEvery 2 daysโ€”
AdsNoNo
In-app purchasesYesYes
DevicesiPhone, iPadiPhone, iPod
Requires iOS16.615.1 โ€” better
Further details โ€” not scored
Size70 MB39 MB
Age rating4+4+
DeveloperSigma DomainGunjan Kejriwal

In-app purchases

2 purchases

Sigma Domain

Subscriptions1
  • Standard Monthly Sigma Domain$5.991 Month
One-time1
  • Additional Usage - Sigma Domain$9.99
3 purchases

Thinkdo AI

Subscriptions3
  • Beginner$4.991 Month
  • Thinkdo AI Pro Plan$9.991 Month
  • Thinkdo AI Pro Max Plan$24.991 Month

Questions

Is Sigma Domain free?
Sigma Domain is free to download, with in-app purchases available.
Is Thinkdo AI free?
Thinkdo AI is free to download, with in-app purchases available.
Do Sigma Domain or Thinkdo AI have ads?
Neither Sigma Domain nor Thinkdo AI shows ads.

Other comparisons