There may be an undocumented Google user agent named GeminiiOS. GeminiiOS is apparently used when a user clicks on a source link from the Gemini app on their iPhone.
This user agent was spotted by Natzir who posted about it on X.
While Natzir was analyzing his access logs, he found an undocumented user agent string “GeminiiOS” that didn’t appear anywhere in Google’s or public documentation. After he did some digging, he was able to confirm that it corresponds to visits generated from the WebView embedded inside the Gemini app on iOS.
This means that when a user is using Google's Gemini app on their iPhone and clicks on a source or link, the page opens within the app’s internal browser is identified under the user agent of GeminiiOS.
The example user agent Nazir sent me was:
Mozilla/5.0 (iPhone; CPU iPhone OS 18_7_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Mobile/15E148 GoogleWv/1.0 (WKWebView) GeminiiOS/1.2025.4170000
He shared this on X:
He even sent me a screenshot of what the web view looks like for this site when this user agent is used:
So if you see it, that is what it likely is.
Forum discussion at X.
