Android Question service and battery consumption notifications

[3394509365]

I have created a service that works in backgound that every 5 seconds reads the values from a sensor on arduino.
Each time (therefore every 5 seconds) he sends me a notification on the phone with the current value read.

If instead of every 5 seconds, do I send the notification only when the sensor value exceeds a certain threshold, is it consuming less battery or is it not influential?

and I noticed that when the phone goes to standby the notifications stop

 

[Erel]

The notification itself doesn't affect the battery.
Other things that your app is doing can affect the battery.

 

[3394509365]

it is clear thanks

But why does the service stop when the phone goes on standby?

 

[Erel]

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