Sensorevent.timestamp To Absolute (utc) Timestamp?

I question myself what the timestamp in SensorEvent.timestamp means. Numbers like 3548712982000 occur. It is not plausible for anything: nanoseconds/milliseconds since 1970 etc. Is

Solution 1:

Just a few seconds after this question on SO I found the answer:

See comment #18 of this issue where it's said that these are nanoseconds since boot (SystemClock.elapsedRealtimeNanos()).

The android documentation definitively needs an update. The doc issue has been recently reported again, feel free to star it.