Can you share minecraft maps?

I play minecrafts povket edition, (android) with my brothers and we can join eachothers worlds but only thru Wi-Fi. And well i'm leaving town and i wanted to know if there's any way they can join me or i can join them without the Wi-Fi

I'm not sure about pocket edition, but on pc you can go into your files, and there's a folder for maps which contains all your maps. Maybe try going to your file manager, press the options button, select 'more', press 'settings', then tick the box that says 'show hidden files'.
Now try looking around in your files for your minecraft maps. I have no idea where they might be so i'm no help here (maybe google it?)
if you find it, copy it and put it somewhere easier to find (like in your music folder or something) then you should be able to send it to your brother via bluetooth or something like that. If you can't, you can connect your phone to your computer, move the world onto the computer, copy it there. Then connect your brothers phone to the computer and put the copy into his maps folder on his phone, and then put yours back where you found it on your phone

EDIT: Just re-read your question and realized your wanting to play together, not just share worlds (all that typing for nothing). On pc minecraft you can host an online server that you can both join, but i have no idea about pocket edition, sorry.