Firefox
Firefox is overwhelmingly a desktop browser.
- Mobile Usage (as a percentage of its total user base): While exact figures for "percentage of Firefox's own users" are less commonly published directly, we can infer from its very low global mobile market share (around 0.5-1.5%) and its higher desktop market share (around 5-7%) that a very small minority of Firefox users are on mobile devices. It's likely in the range of less than 10-15%, and possibly even lower. Its strength and history are firmly rooted in desktop Browse.
Google Chrome
Chrome is dominant on both platforms, but mobile contributes a larger share to its overall user base.
- Mobile Usage (as a percentage of its total user base): The data consistently shows that Chrome's mobile usage (smartphones and tablets combined) makes up a significant majority of its total user base. Given that mobile internet traffic is 60%+ of overall traffic, and Chrome commands a large share of both mobile and desktop, it's clear that well over half of Chrome's users are on mobile devices. Estimates suggest this figure is around 60-70% of its total users are on mobile (primarily smartphones).
Apple Safari
Safari's user base is heavily, almost exclusively, mobile.
- Mobile Usage (as a percentage of its total user base): This is where Safari stands out. Because Safari is the default browser on iPhones and iPads (iOS and iPadOS), its user base is overwhelmingly mobile. Its global mobile market share is around 20-23%, while its global desktop market share is only 7-9%. This indicates that a very large majority, likely 75-85% or even higher, of Safari's total users are on mobile devices (iPhones and iPads).
Others
It's worth adding that an estimated 20-40% of Brave's user base is mobile and 20-30% of Vivaldi's.