Sigma AI Browser review

Best for

Privacy-focused users who want local AI with an agent on top

Price

Freemium
Free: Free browser with AI chat and local AI

Platforms

Mac, Windows, iOS, Android

Made by

Sigmabrowser OÜ, Tallinn, Estonia

App store ratings

iOS 3.4★ (7)

What it is

Sigma is a Chromium-based browser from Estonia that combines an AI agent for web tasks with Eclipse, a local AI model that runs on your device without sending data to the cloud. It also offers AI chat, chat with the current page and a deep research mode, plus a built-in ad blocker.

Latest: Sigma reported a surge in offline, local-AI use in April 2026.

What the AI does

• AI agent for forms, bookings and workflows
• Eclipse on-device AI model
• Chat with the current page
• Deep research mode
• AI chat and image generation

Pros and cons

How it scores

Interesting privacy-first design, but there's little independent evidence on how well the agent works.

Feature checklist · 6 of 9

• ✓AI agent that clicks, types and completes tasks on websites (yes)
• ✓Summarise or chat with the page you're on (yes)
• –Ask questions across several open tabs (no)
• ✓Useful AI features free without a subscription (yes)
• –Choice of AI models (no)
• ✓On-device or local AI option (yes)
• –Connects to email, calendar or work apps (no)
• ✓AI browser on iPhone and Android (yes)
• ✓Available on both Windows and Mac (yes)

How we score apps →

Alternatives

See all Sigma AI Browser alternatives, ranked →

• Perplexity Comet 8.7/10People who want the most capable free AI browser on every device
• Google Chrome with Gemini 8.2/10Chrome users who want AI help without switching browsers
• Microsoft Edge with Copilot 8.0/10Windows and Microsoft 365 users who want AI in the browser they already have
• Brave Leo 8.0/10Privacy-minded people who want a free AI helper in a fast everyday browser

Perplexity Comet vs Sigma AI Browser

Sources

• Sigma AI Browser
• I tested the top AI native browsers in April 2026 (Composite)
• Sigma AI Browser on the App Store