In multiplayer, chunks do not properly load for the client. The only way to load the chunks that do not show up properly is to go through the rather time-consuming process of unjoining and rejoining the host's world. This is quite annoying and is found, to my knowledge, on iPhone 4S as well as iPhone 6 devices.
MCPE-8797
Chunk loading in multiplayer is complicated
Resolved
Duplicate
1
Confirmed on iPad 2 and iPad mini (1) running iOS 8.3. The only things which appear in the unloaded chunks are entities.