I personally recommend you using an app named MCPE Addons.
It should have a picture of a steve and a zombie on it's icon.
It has amazing addons such as the More Problems mod, with incubators, drones, combat drones, new bosses including Sandworm, Fallen Angel and frost worm and it even has new types of pillagers.
Also you can download maps and texture packs but that is irrelevant.
Keep in mind, not all of the addons on it work but the majority do.
APPLY TO JOIN MY NEW MCPE REALM