How to Install Mods
Step 1: Locate the mod you want to install.
Step 2: Download the file on your computer. (If it's a ZIP file, extract it.)
Step 3: Download PocketTool or BlockLauncher to your Android device.
Step 4: Connect your device to your computer.
For PocketTool: Copy the mod file into the PocketTool patch folder ("mnt/Android/data/com.snowbound.pockettool.free").
For BlockLauncher: Copy the mod file into any folder you want.
Step 6: Open PocketTool or BlockLauncher.
For PocketTool: Select Tool Kit -> Patch Mod and choose the mod that you downloaded. Hold the mod, and a message asking if you want to patch it should appear. Tap it. Go to the settings in PocketTool and select "Apply Changes". (If you get a warning asking to uninstall MCPE, don't worry. It will immediately reinstall it with the mod included.)
For BlockLauncher: Open MCPE and click on the wrench at the top of your device. It will show a menu - click on "Manage ModPE Scripts". It will show another menu - click "Import", click on "Local storage" and find the mod you downloaded. When you tap it, it should bring you back to the window before and you'll see the mod now imported. Hold the mod and click on "Install".
Step 8: Open a world or create a new one and try out your newly installed mod!