Incredible! I've installed Garmin Connect Mobile on different devices now and NEVER saw an app like that: all devices get warm and their batteries get empty very soon.
On newer Samsung devices, the Smart Manager pops up after some days, that is has found a suspicious app using to much power, the Android Assistant show RTCPU values which are never (!) lower than 10% on all devices.
The actual battery statistics on my tablet I am using just now brings up 92% of the power consumption is needed for GCM, and only 8% for everything else (display, Android system, google services, the browser etc.)
What's going on here?!