Still can't find information, my idea is totally wrong??
If you want to keep objects still,
You should use latitude and longitude??
almost 5 years ago
Use AR.RelativeLocations if you want to have objects permanently close to the user, e.g. an animated dog should always walk nearby. As far as I understood you want to "drop an item next to the user", it should stay there and not follow the user's steps. You need to use AR.Location instead and implement the AR.context.onLocationChanged to get lat/lon of user when "dropping the item".
Hope that helps Best regards
PS.: Note that JS onLocationChanged event fires when location was set in native code (architectView.setLocation...)