Step 1: Download iExplorer.
Step 2: Plug your iPod/iPhone/iPad into your computer.
Step 3: Download your favorite x16/x32/x64/x128 texture pack, and extract the terrain, gui, default_world, background,
icons and particles
Step 4: Open up iExplorer and go here:
Step 5: Drag all the files you extracted into the iExplorer Window
Step 6: PROFIT!