On Android devices the ability to save
Minecraft worlds (maps) might not be available from within the game, the an option to
Export isn't shown when looking at a given world (just Duplicate or Delete). To solve this, Minecraft worlds created on mobile (Android) devices,
need to be accessed directly through Androids system, or other,
File app to browse to the location worlds are saved by default. Typically this is;
Internal storage > games > com.mojang > minecraftWorlds
However, depending on the device setup, whether it uses additional storage via an SD card and how that is itself set up, i.e. Minecraft is installed to the card rather than device internal storage), that location might not exist or cannot be accessed. If so, check to see if the Minecraft 'world' can be found in the following location;
Internal storage > Android > data > com.mojang.minecraftpe > files > games > com.mojang > mincraftWorld
Here, worlds will listed as uniquely named folders that can be saved clicking the 3 'burger' menu dots to the right of each instance and selecting an appropriate option, typically
Copy to or
Quick Share; selecting
Copy to files can be sent to others via app sharing, Discord, Whatsapp etc. -
note that as Minecraft worlds are basically stored in folders they may need to be 'archived' before sending else the folders contents will be sent as individual files.
If this doesn't work either, in the
File app use the search feature to find references to "
mojang" and investigate within for further references for "
data" or "
game" locations where world data should be saved.