I have got a small application that uses compass readings on my device (Xperia Neo V). When testing it, I got very satisfying results while pointing the desired direction. But I tested it on a Samsung Galaxy S3, and I run the same application on my neo V at the same time, the two devices did not show exactly the same direction. There was a drift about 10 degrees.
So, as an electronical engineer I know that different digital compass sensors may give different values due to design, but I coulnd't find an efficient solution to that yet. Any Ideas?