Thanks for the swift answer. I am already using the API via device ID and it works like a charm, so first of all thanks for that :).
What I was asking was if you implemented already a filtering function for geographic coordinates, or if it was necessary to parse all devices and then filter them via a script to have only the device within a certain range of a geographic coordinates.
I can see that you can filter for user, id names, and city but cannot see any filter with coordinates.
As an example you will find below the similar URL in luftdaten:
URL= "http://api.luftdaten.info/v1/filter/area=50.867416,4.377298,0.3" # geocoordinates and 300 meters around
I hope this clear things up,