The SOS/call buttons can be used to validate the device is on. A short press on any of them will light up both LEDs.
The small button on the left side of the device by the USB port is the power button. The power button is disabled to avoid it accidentally being powered off.
To turn the device off, if needed, use the app shutdown feature. However, it is recommended to keep the device on at all times as powering off requires some time for the GPS to lock on location, especially when indoors.
When using 2-Way Voice (AngelCall), the volume buttons will turn the speaker volume up or down, otherwise, these buttons are not active.
With the Call Request feature, pressing the SOS/Call buttons can also send a notification that your child is requesting a call from you.