Sensor fusion script for ios?

I'd like to map orientation and position change of the iPhone as accurately as possible onto a gameobject. Doing this as good as possible requires sensor fusion with kalman filters and smart value integration and so on. As this is a quite common demand I'd expect there to be some well tweaked solution that does exactly this work for me. But after an hour of googling I didn't find what I was looking for. Can anyone point me to some free/paid script/plugin that outputs accurate, drifting corrected position and orientation output on iOS?