SOLAR COMPASS includes cardboard busola and string and an app that requires you to enter the shadow angle measured whilst pointing the busola to the target and using the string as gnomen. Works fine. A simpler approach is to have a sticker of a protractor, if you have one. I showed tools i used, but at the very least you can tear cardboard in any shape and use cap of ginger beer bottle (only this bottle; do not know why only this bottle cap) to make markings and draw an arrow extending outwards from 0 degrees and pointing to target direction.














