In the mobile version of Terraria, there is a tutorial mode. It is a quick introduction to terarria, but it has secrets in it. Here are some basic notes.

Only biomes are underground, purity, and underworld. Nothing else

A possessed armor spawns far on the left of the floating island, below it.

Players can't die from monsters

Players are named student

A vulture always spawns after creating your house.

There is an obsidian barrier, with lava.

So I was exploring the floating island, and decided to build a hellevator. The water from the hellevator spread on the lava barrier, and created obsidian on it. Mobs spawned on the obsidian path, including 2 nymphs. I was lucky to find undead miners to harvest their bombs, because I had no pickaxe to break the barrier. Once I broke through, I jumped down into the underworld. The underworld is nothing but a large pool of lava, sadly.

When exploring the far left of the island, there is a lucky horseshoe in a chest, I also got a chain knife from a cave bat. I will add the images I took soon.

I realized that I haven't explored some other things (Whatever you do in this mode doesn't save), Like finding sky islands (there might not be any), exploring the far left or right of the world (I tried, it was too far), and maybe creating an obsidian bridge in the underworld, finding a voodoo demon, and maybe fighting the wall of flesh (considering how monsters can't kill the player, the same might apply for this boss).