The default controls are designed for gamepads and mouse/keyboard. You can move and aim independently. Use the left stick or WASD to move and the right stick or mouse to aim. In this mode, the ship moves instantly in the direction you move the stick. Ship rotation is visual only and can be ignored.
Try Classic controls for an added challenge. This mode requires you to rotate the ship in the direction you want to move or shoot and then apply thrust. Rotation is a vital part of movement in Classic mode.