Empatica EmbracePlus Instructions For Use Manual page 38

The Empatica heart will be visible if EmbracePlus is connected to the
companion app/system via Bluetooth, and not visible if it is
disconnected. Although EmbracePlus can work stand-alone for several
hours, the more it stays connected to the companion app/system, the
better. This ensures that the recorded data are always synchronized.
EmbracePlus transmits raw data over standard Bluetooth Low Energy
5.0. Physiological parameters are computed by the Companion
app/system, rather than on the EmbracePlus.
EmbracePlus will continuously collect sensors raw data.
If the EmbracePlus is removed from BLE range, it will store sensor data
internally for a maximum of 24 hours. After 24 hours, no further sensor
37