The other side of the board has a bq24024 lipo charger, a L3GD20 3-axis gyro (just like the one we carry!), and LIS3DH 3-axis accelerometer.
To save costs, the designers used the CC2540 as both a BTLE controller and the microcontroller that reads all the sensor data from the gyroscope & accelerometer and decides whether it's time to activate the help function on the paired phone.