this thing doesn't seem to have a magnetometer or a barometer, it's just an accelerometer and a gyroscope. not even very good ones, they're probably on par with what your cellphone has, if not worse
i think some enterprising company (possibly Shenznen Firepower Control Co. Ltd. based on @poppyhaze's research) has realized they can make a lot of money selling ADIS16488-style devices that only barely work at a half of their sticker price from AD