I've felt this same sentiment recently, but regarding the Chrome browser for Android. It used to be perfectly fast, but over time (with updates) it just seemed to get slower and slower on my Galaxy S4, to the point where now it sometimes can take fifteen seconds to register a scroll event on a site like Reddit. Heavier sites are practically unusable. Even as I type this, I see my characters suddenly appearing in groups of twenty or so at a time, where several months ago it was not a problem. And I never even have more than three tabs open normally.