"By enabling Location Services for your devices, you agree and consent to the transmission, collection, maintenance, processing, and use of your location data and location search queries by Apple and its partners and licensees to provide and improve location-based and road traffic-based products and services."
It will also send your location to Apple when no app is requesting your location:
"If Location Services is on, your iPhone will periodically send the geo-tagged locations of nearby Wi-Fi hotspots and cell towers in an anonymous and encrypted form to Apple, to be used for augmenting this crowd-sourced database of Wi-Fi hotspot and cell tower locations."
Unlike on Android, you cannot get your location without sending this data to Apple:
"To use features such as these, you must enable Location Services on your iPhone"
It will also send your location to Apple when no app is requesting your location:
"If Location Services is on, your iPhone will periodically send the geo-tagged locations of nearby Wi-Fi hotspots and cell towers in an anonymous and encrypted form to Apple, to be used for augmenting this crowd-sourced database of Wi-Fi hotspot and cell tower locations."
Unlike on Android, you cannot get your location without sending this data to Apple:
"To use features such as these, you must enable Location Services on your iPhone"
https://support.apple.com/en-us/HT207056