As we all know, not all web browsers are the same. That's generally a good thing because we want diversity and creativity to drive innovation; but it also means some of the most beloved features in one browser may not be implemented in other browsers for a long time, if ever. This has been the case for a long time with one of Chrome's somewhat hidden power user features: swiping to change tabs. But if you're a Firefox user, you can look forward to getting this awesome feature fairly soon.
Tab switching with a swipe is generally more efficient than most other methods since you don't have top tab a button, and then find the destination tab on a new screen. This is great as long as you don't have to swipe through too many tabs, though you may still want to open the full tab switching screen if you've got a dozen or more tabs open.
If you install the recent nightly Android builds of Firefox, you'll find that the swipe gesture on the address bar is now supported. The final code was added July 22nd, and the July 23rd build was the first to include it. There aren't any settings or flags to change, so swipes across the address bar will work right away with the update.
The development team is still watching issue reports for possible bugs or problems with the implementation, but the feature appears to work properly, so this will likely pass through the beta releases fairly soon, then hit the stable channel eventually.
As usual, you can install the latest version of the Firefox nightly build from the Play Store, or download it from APK Mirror.