It's somewhat perceptible. The worst, for me, is the search for apps, which visibly lags. My battery has been replaced and shows 99% capacity. This is an iphone

It's somewhat perceptible. The worst, for me, is the search for apps, which visibly lags. My battery has been replaced and shows 99% capacity. This is an iphone 7 with the latest ios upgrade it can get, 15.6.something IIRC. I think another issue is that apps do tend to get more sluggish, since they probably expect to be running on newer hardware. If you stick to an older ios version, if they're deemed incompatible, they won't update. But as soon as you're on the latest ios, you get the app updates, too, if you've left the default on. Google maps, for example, is clearly more sluggish than before. Apple maps is practically unusable. Youtube crashes reliably (but works fine in the browser...)