General-purpose hex editors available on the Google Play Store can be used to manually manipulate save values if you know the specific hex offsets for items or Pokémon data. How to Edit Your Save File
is a recommended alternative if you prefer not to install an APK. It runs in a browser and supports editing party, PC boxes, bag items, and trainer data for Generation III games like Fire Red. Hex Editors: Pokemon Fire Red Save Editor Android
While there isn't a single "standard" paper on this topic, editing Pokémon Fire Red General-purpose hex editors available on the Google Play
save files on Android is primarily achieved through specialized mobile applications or web-based tools that modify Key Save Editors for Android PKHeX (Mobile/Android Port): A mobile version of the popular PC tool, Pokemon Fire Red Save Editor Android