Here are some tips to help remove the jittery/choppy mouse movements in your gameplay.
In the K2 App Device page set the mouse DPI setting to the maximum resolution for your mouse.
Set your mouse to the maximum DPI setting.
In your game menu, set the look sensitivity to maximum.
Adjust the deadzone. Make the deadzone as small as possible until your character is looking around without you touching the mouse. If the deadzone is set to large, your movement will be jittery with smaller movements.
Adjust the mouse sensitivity in the K2 App to what feels best for your style of play.