You have good eyes. That chip could be a magnetometer, it is obviously
connected via I2C or SPI to the microcontroller and the markings seem
vaguely similar to the Honeywell chip in DK1. However, without a
higher resolution picture it is impossible to say. Someone has
demanded to know the markings on the chip in the comments, so lets
see. Hopefully I was wrong and they didn't remove the magnetometer, it
would be stupid to do so.
However, it isn't used for tracking anyway - without being able to
calibrate it (which is disabled in the configuration tool) are the
values useless. Also the sensor fusion most likely isn't using it,
unless there is a big difference between the 0.3.2 SDK and 0.4 one -
the magnetometer data are disabled in the 0.3.2.
J.