We need this permission to allow you to plan a journey from your ‘current location’ and to show you your live location on the interactive map.
If you choose not to share your location you can still use the GoSESTRAN app, but you will have to enter your current location manually each time you plan a journey.
You also won’t be able to see your current location on any of the interactive maps without allowing the GoSESTRAN app permission to use your device location.