Accelerometer data that is received from multiple accelerometers can be synchronized to identify a known movement. This synchronization occurs in real time as the accelerometer data is received from the multiple devices. The orientation of an accelerometer can be compensated for dynamically. By dynamically compensating for the orientation, the user can wear the accelerometers in various orientations without needing to calibrate a portable computing device to account for a particular orientation. Portable devices can have one or more detachable accelerometers. The accelerometers can be detached and placed at virtually any location of a users body to allow for the detection of custom movements.
