Yab

SigmaOS vs Opera Neon

We make Yab, the third column.facts checked Oct 9 ↓

SigmaOS is a Mac browser on WebKit that treats tabs like a to-do list, in workspaces down the side, with an AI assistant called Airis.

Opera Neon is Opera’s agent browser for Mac and Windows. Its own agents act in your live session on a $19.90 plan, and since August 2026 outside agents like Claude Code can use it free through its MCP Connector.

The short answer

Pick SigmaOS
  • if you want workspaces and tabs you mark done, on a Mac
  • if you browse by keyboard, with single-key shortcuts
  • if you prefer WebKit to Chromium and want spaces
Pick Opera Neon
  • if you want Claude Code or another MCP client to use a real signed-in browser, free
  • if you want one plan for an in-browser agent, deep research and making apps and media
  • if you want a VPN and an ad blocker built in
Or Yabours
  • if you miss Arc and want spaces, pins and folders kept, on a Mac
  • if you already pay for Claude or ChatGPT and want it to work in your signed-in tabs
  • if you want Claude Code, Codex or Cursor to drive a real browser over MCP

At a glance

SigmaOS and Opera Neon, with Yab beside them for a Mac.

SigmaOS vs Opera Neon
WhatSigmaOSOpera NeonYab
Made bySigmaOS Inc. (London)OperaSerafim Korablev
StatusNo release notes since February 2025UpdatedUpdated
Runs onMacMac and WindowsMac
Phone appNone; Mac only. iOS has been on its roadmap since 2021None yet; Opera says a mobile version will come, no date givenNot yet
PriceFree; Personal Pro $20/month or Personal Max $30/month for more AIFree, and free for outside agents; Opera’s own agents $19.90/monthFree; its AI runs on your own Claude or ChatGPT plan
AIChat about pages, on its own AI serviceAn agent that works in pages, on its own AI serviceAn agent that works in pages, on your Claude or ChatGPT plan
Driven by outside agentsNoMCP and a command lineMCP and a command line
EngineWebKitChromiumWebKit
Tabs down the sideYesNot statedYes
SpacesYesYesYes
Split ViewYesNot statedYes
ExtensionsChrome Web StoreNot statedChrome Web Store
Ad blockerBuilt inBuilt inBuilt in
Open sourceNoNoNo

Checked October 9, 2026 on each maker’s own pages, linked under Sources. Prices are per month, in US dollars.

Where they differ

What separates them, area by area. Where one plainly has more, it says who; where it comes down to taste, it says so.

AIOpera Neon leads

Only Opera Neon has an agent that clicks, types and finishes tasks in your pages. Airis chats about the page you are on, sums it up, looks things up and translates; no agent. Neon Chat talks about your tabs, Neon Do acts in your live session, research agents dig, and Make builds apps and media on Opera’s servers.

Agents like Claude Code and CodexOpera Neon leads

SigmaOS has no MCP server or command line for outside agents. Opera Neon can be driven over MCP and a command line, through its MCP Connector, read-only unless you allow more, and opera-browser-cli.

Tabs and windowsSigmaOS leads

SigmaOS has tabs down the side, spaces and Split View. Opera Neon has spaces.

Priceeven

SigmaOS: Free; Personal Pro $20/month or Personal Max $30/month for more AI. Opera Neon: Free, and free for outside agents; Opera’s own agents $19.90/month.

Where it runsOpera Neon leads

SigmaOS runs on Mac. Opera Neon runs on Mac and Windows. On a Mac, SigmaOS needs macOS 12 or later. SigmaOS has no phone app: Mac only. iOS has been on its roadmap since 2021. Opera Neon has no phone app yet: Opera says a mobile version will come, no date given.

Engine and extensionsa matter of taste

SigmaOS is built on WebKit, the engine Safari uses; Opera Neon on Chromium, as Chrome is. SigmaOS takes extensions from the Chrome Web Store, Opera Neon none.

PrivacyOpera Neon leads

SigmaOS has an ad blocker built in. SigmaOS keeps history and cookies on your Mac unless you turn on sync, stored encrypted on AWS; its privacy policy doesn’t say where Airis requests go. Opera Neon has an ad blocker built in and a VPN. Page content used with Neon’s AI goes to Opera’s and OpenAI’s servers, kept up to 365 days; passwords, cards and cookies stay on your device.

UpdatesOpera Neon leads

SigmaOS: Still downloadable, with no public release notes since version 1.19 in February 2025. Opera Neon is updated as usual.

What their pages don’t lead with

Real limits, from the makers’ own words and our own use.

SigmaOS

  • Mac only
  • No public release notes since version 1.19 in February 2025
  • Chrome extensions only partly work, behind its WebKit+ option
  • Its AI is an assistant, and regular use needs the $20 or $30 plans

Opera Neon

  • Opera’s own agents need the $19.90 a month plan
  • Mac and Windows only; the phone version isn’t out
  • Its AI and the MCP Connector need an Opera account
  • Page content used with its AI goes to Opera’s and OpenAI’s servers, kept up to 365 days

Yab, honestly

  • Mac only: macOS 15.4 or later, no Windows, iPhone or Android
  • New: first released in September 2026
  • Its AI needs a Claude or ChatGPT plan; ChatGPT’s free plan may work with low limits
  • WebKit, as in Safari: a site tested only in Chrome can misbehave
  • Closed source

What changed lately

  • August 12, 2026Opera Neon: Free plan: outside agents can use Neon without a subscription
  • May 12, 2026Opera Neon: opera-browser-cli command line released
  • March 31, 2026Opera Neon: MCP Connector lets outside AI clients act in Neon
  • February 4, 2025SigmaOS: Version 1.19.0, a performance update, the last release with public notes

Questions

Is SigmaOS free?

Yes, with limits on its AI. Free; Personal Pro $20/month or Personal Max $30/month for more AI.

Is Opera Neon free?

Yes, with limits on its AI. Free, and free for outside agents; Opera’s own agents $19.90/month.

Which has an AI agent, SigmaOS or Opera Neon?

Opera Neon. Airis chats about the page you are on, sums it up, looks things up and translates; no agent. Neon Chat talks about your tabs, Neon Do acts in your live session, research agents dig, and Make builds apps and media on Opera’s servers.

Which runs on Windows, SigmaOS or Opera Neon?

Opera Neon does. SigmaOS runs on Mac.

Do SigmaOS and Opera Neon have phone apps?

SigmaOS has no phone app: Mac only. iOS has been on its roadmap since 2021. Opera Neon has no phone app yet: Opera says a mobile version will come, no date given.

Is SigmaOS still being updated?

Still downloadable, with no public release notes since version 1.19 in February 2025.

Is there a third option on a Mac?

Yab, Yet Another Browser, is free for the Mac: tabs down the side with spaces, folders and Split View, as in SigmaOS; an agent in your signed-in tabs like Opera Neon’s, on the Claude or ChatGPT plan you already pay for. Claude Code, Codex and any MCP client can drive it too. It runs on WebKit, the engine Safari uses, and takes Chrome extensions. It is Mac only, and new.

More comparisons

SigmaOS vs ArcSigmaOS vs VivaldiSigmaOS vs ZenSigmaOS vs OrionSigmaOS vs ChromeSigmaOS vs SafariSigmaOS vs EdgeSigmaOS alternativesYab vs SigmaOSOpera Neon vs DiaOpera Neon vs CometOpera Neon vs AtlasAside vs Opera NeonOpera Neon vs ChromeOpera Neon vs SafariOpera Neon vs EdgeOpera Neon alternativesYab vs Opera Neon
Sources, read October 9, 2026. Something out of date? Write to hello@serafimlabs.io and we fix it.

Yab, Yet Another Browser.

Free for the Mac. Arc’s sidebar, your own Claude or ChatGPT as the agent, Chrome extensions on WebKit.

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