This is now the interesting side of the PCB:

You can see the 3D antenna here

The device is powered by a Nordic Semi N51802. These Nordic Semis are quite common on Logitech peripherials.

In addition to that, a SkyWorks 2438T Zigbee and Smart-Energy Module is right next to it.

The Gyro and Sensing Unit is a IC268G from InvenSense

Last but not least, the LiPo battery is a 80 mAh jobby with 4.2V and 0.3 Wh

This is a composite picture. The lighting is so odd, because you should be able to read all the part numbers :)