and take parts off seed,s you have make before and put them in a custom seed.
the only thing i do not no what part you take out thats a suprise. but if yourluky
you put a part whit a cave in it. you must try it to find it out what part of the world
but i think the top part of the hexnr list in the editor is the left side in the world
when you spawn the first time in it but i do not no that.
this work on all minecraft PE on ipad,iphone and android syteems.
you do not have to have a jailbreak or root phone it work whit out it.
of this work on the pc version i do not no.