Just to mention that i had the audio coach set to announce the temperature plus other metrics every 1000m. Depending on the activity, that's every 5 to 10 minutes. I assume that locus pings the sensor for temperature at that point. This is not enough to keep the sensor communication "awake". As a work around I wouldn't mind the audio coach bringing the phone screen on if that's all it takes. Currently I've given up on this in LM4, and record all my activity metrics in a different app now.