how to download garmin explore maps to phone/tablet SD card

I'm able to download maps on my phone and tablet using Garmin explore, but I don't see a way to tell the app to store the map files on the SD card (external storage) rather than internal storage.  I'm OK for now, but if my tablet starts getting filled up with too many maps I'd like to be able to store everything on a removable SD card instead of using internal storage, is there a way to do that?