How to transfer a minecraft world to another device?

How do I transfer a mc pocket edition world from my phone to my tablet (both are android)?

I tried connecting my phone to the computer to see if I could transfer the files out, but the computer isn't recognizing the usb driver for my phone… Is there another way to transfer the world?

The only way I know you can do it with is on a computer but you would need to put it on a flash drive