On Friday, 4 June 2021 at 14:19:20 UTC+1, NY wrote:

It says the "Location is computed on the handset" - does this mean that GPS
must be turned on, or does it use some other technology? Maybe ELS
temporarily turns on GPS even if it is turned off in the phone's pull-down
menu of receivers (GPS, Wifi, mobile data, Bluetooth).

On Android the location API provides a 'fused' location service i.e. it combines information from multiple sources to improve/maintain accuracy depending on what sources - such as GPS, known WiFi APs, GSM cell IDs etc - are available. It'll temporarily override any Location setting you might have previously set, unless you've disabled the ELS functionality entirely whose setting that will be honoured. The mobile provider might still provide cell tower triangulation location information but it is much less accurate (particularly if there aren't enough visible towers to triangulate against).