Clear large areas of blocks, drain oceans, or build massive structures instantly.
Open the native Files App > On My iPhone/iPad > Terraria > Worlds
Free mobile options — realistic expectations
Internal Storage > Android > data > com.and.games505.TerrariaPaid > Worlds . iOS: Files App > On My iPhone > Terraria > Worlds . How To Get A Mod Menu For Terraria Mobile! (TL Pro Review)
is the most popular, free interactive map viewer. It is not an editor that lets you place blocks, but it is an indispensable tool to find anything in your world instantly.
Ensure the editor you use supports the current mobile Terraria version (currently matching Desktop 1.4.4+ journey's end updates). Using an outdated editor will break the file.
(Web-based, works on mobile browser)
iOS is more locked down, but it works via iTunes File Sharing .
The only catch is that it's primarily a character and inventory editor, not a full map editor. But it's the perfect free tool for iOS users looking to tweak their characters.