Alternate reality
A display compass was a device on a thruster suit that enabled a user to alter their trajectory by degrees.
In 2259 of the alternate reality, Hikaru Sulu advised an off-course James T. Kirk to correct his course by 37.243°. When Kirk's display went dark, Spock informed Kirk that it would be mathematically impossible to hit his target (the door of USS Vengeance) without his display. Kirk then criticized Spock's poor bedside manner. Khan Noonien Singh, whose display continued to function, then advised Kirk how to adjust his course. (Star Trek Into Darkness)