I've notice that Z2 have some tactil lags... and, as if that not enough, i broke my tactile panel... (falling from 20 cm).
So I've buy a panel "screen+tactile" and replace it.
Result: Same as before
But, today, i found a apk called : SGS touchscreen booster on playstore
That's make some good changes!
It's not perfect, but i think it's a good start ^^