AI Chat answers and writes in any tab, and Chat With Page turns any article into a conversation.
Switch to Incognito mode and your history and cookies vanish the moment you close the tab.
The built-in ad blocker cuts ads and trackers on every site, no extensions needed.
AI Chat syncs across your devices: ask on your iPhone, continue on your desktop, and never lose a conversation.
Sigma puts AI chat right in your iPhone web browser: ask questions, summarize articles, and chat with any page. No separate apps, no subscriptions.
Learn more about AI ChatLearn more about Chat With Page
Sigma is a private browser for iPhone with Incognito mode built in: open an Incognito tab, browse what you want, and the whole session disappears when you close it. Private browsing on your iPhone takes one tap, right from the start page.
Learn more about Private Browser
Sigma ships with a free ad blocker for iPhone: pages load cleaner and faster, trackers are cut, and you don't need extensions or separate apps.
Sigma is the iPhone web browser that blocks ads, protects your privacy, and answers your questions. All free.
Get Sigma free, no account needed.
Open iPhone Settings → Sigma → Default Browser App, and links will open in Sigma.
Tap AI Chat on the start page and ask anything.
