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Spyglass is an app for iPhone. It overlays the camera live video image with the compass direction corrected for magnetic declination.
Stepper motors and servo motors have strong permanent magnets. You need to keep any compass including a smartphone app electronic compass away from the mount. I stand about 2m behind the mount, move until the centre of the mount is between me and the point on the horizon due south which is visible on the phone/iPad camera image.
Lay the dec axis horizontal and providing your optical axis is parallel to your RA axis (no cone error) then you can use finder and prime optic to point the RA to the point on the south horizon.
Another method
If you always observe from exactly the same spot, drift align the mount precisely once. Level the dec axis and use the prime optic to spot or photograph the horizon point. Use the photo next time to point the RA.
If you want to use an orienteering compass, go to an outdoor store. Price is usually a good indication of quality. Brands like Suunto and Silva are the old favourites. They've been around forever.
Joe
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