title: Android IMU accuracy
body: <p>I'm working on a project with the goal of tracks animals from a hill. In the first field season we used using OpenTags and a calibrated camera, which worked but required extensive processing/calibration and-crucially-did not provide any visual feedback when the system went awry. </p>
  
  <p>Since one of the goals of the project is to make it easy for other biologists to repeat,I'm investigating using the gyro, magnetometer, and accelerometer already in smartphones. Then, using an app or some simple post processing transfer this to roll, pitch, and yaw.</p>
  
  <p>My question is regarding the accuracy of the smartphone vs an OpenTag. In order to track animals at distances greater than 200m, the system must have sub-degree accuracy and, more importantly, low noise. I've been looking at the Sensor Kinetics app but I find that the pitch/yaw/ heading values tend to drift more than is acceptable. I'm not sure if this is a filtering issue or an issue with the sensors themselves. </p>
  
  <p>Does anybody know where I might find this type of data and/or recommend phones and apps that easily provide these data with little additional processing?</p>
  
  <p>Thanks! </p>