Compensating compass lag with the gyroscope on iPhone 4

Question

I\'ve been experimenting with the compass and gyroscope on iPhone 4 and would like some help with an issue I\'m having. I want to compensate for the slowness of the compass

Answer 1

Answer to question 1 is Yes, question 2 you are on the right track but you could use a variable name that is not 'horizontal', question 3 is answered by hotpaw2 and also a yaw in a chopper or helicopter at near zero altitude would alert the pilot with an alarm. There is a time lag because part of the software is local while there are other factors which can slow it down including access to a sensor for detecting magnetic waves, the device position and direction, preparing the graphic output for the compass display, computing and outputting data from the gyro and sensors through a relatively slow interface, using a general purpose handheld device not custom designed for the type of task being asked of it.