User blog comment:Bananaman24/Need help!!/@comment-7697305-20131028231247/@comment-7697305-20131030062437

Alright, that's probably why you're having troubles. The terrain is usually the biggest danger when fighting the Wall of Flesh. What most people seem to have found is that the best way to prepare for this fight is to build a large, flat bridge across a portion of the Underworld.

(For a fully detailed guide on soloing the Wall of Flesh, I would recommend checking out this blog post. It was made for the PC version, but I imagine the strategy would be the same for the mobile version.)