Update: There was a typo with the Firefox OS UA in the original post. The last version number in the UA has been corrected to 14.0.
A decision has been reached on the Firefox OS user agent (UA) string. A key point in the discussion about the UA was whether to include an “Android” token to help with mobile Web compatibility. The UA string for Firefox OS will not include any operating system token. Gerv summarized the rationale in the bug:
In absence of any new information, this decision is made. But here is a rationale summary: any OS identifier involving “Android” will lead to bugs like bug 777633 (serving of Android intents), the pushing of “install this Android app!” and other problems. Such problems will continually occur, and evangelising them is hard. UAs with “Gonk” or “B2G” as their OS identifier had the same content profile as UAs with no OS identifier at all. Leaving out the OS means we don’t have to change UAs when we change OS in the future, meaning we have less evangelism to do later. Having it different from Fennec Android makes market share determination a little easier. And finally, having no OS identifier is a strong values statement of “the web is the platform”.
The Firefox OS UA will be:
Mozilla/5.0 (Mobile; rv:14.0) Gecko/14.0 Firefox/14.0
As a reminder, the Firefox for Android UAs are:
Mozilla/5.0 (Android; Mobile; rv:14.0) Gecko/14.0 Firefox/14.0 Mozilla/5.0 (Android; Tablet; rv:14.0) Gecko/14.0 Firefox/14.0
All Firefox UAs are documented in the Gecko user agent string reference.