With the objective of getting phone sensor data and hooking in additional wearable device sensors, it is worth a look at some existing open source applications in this space -- few of which are:
Relayr Proto iOThttps://github.com/relayr/android-proto-IoT * looks interesting, android app on Play store
Purple Robothttps://github.com/cbitstech/Purple-Robot *caveat that it's not being actively developed
Emotion Sensehttps://github.com/emotionsense and previously found on: http://emotionsense.org/code.html
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TODO Comparison matrix.