Same here, lags here and there, the most annoying ones are the stutters that appears when swiping up to close an app, it feels cheap like if i was using an iphone 5 or something, so dissappointed for apples poor optimization. Also it seems like you'rs on the beta program? Can you inform them about this issue on the feedback page?

On god, they should focus on the UI and basically ios performance in general, they just keep releasing features while the optimization is non existant. All they do is accumulate bugs, lags and glitches. iOs is some android level thing now.