All iOS devices I've used have had this issue. That's iPhone 2G, iPhone 3GS, iPhone 4, iPad 2, iPhone 4S, iPad 3, iPhone 5, iPad 4, iPhone 5s and iPad Air. The only thing that differs is the degree of severity.
Hmmm. Well, I never browsed much on my iPhones, so I don't know if any of them had this issue. I think iPad 1 refreshed a lot, iPad 2 a little less, and iPad 3 was just incredible, held multiple tabs no problem. Skipped the 4. Air is just bad, worse than any of the previous iPads, except perhaps maybe the 1.