ModdedPE is a launcher which allows you to open Minecraft PE and load NMods. ModdedPE can also be used as a library for your project.
implementation 'com.github.TimScriptov:ModdedPE:TAG'
implementation 'com.github.TimScriptov.ModdedPE:adal:TAG'
implementation 'com.github.TimScriptov.ModdedPE:minecraft:TAG'
implementation 'com.github.TimScriptov.ModdedPE:xbox:TAG'
implementation 'com.github.TimScriptov.ModdedPE:fmod:TAG'
Here are some samples can help you develop NMods:
https://github.com/TimScriptov/NMOD-Examples
Would like to develop another mcpe launcher which can load NMods?
The Open Source NModAPI will help you a lot:)
https://github.com/TimScriptov/NModAPI