Keep at least 1GB free for extraction and save data.

A "Mod OBB" is an altered version of that data file. Modders take the original file, strip out unnecessary assets (often radio stations, cutscenes, or high-def audio), and compress the remaining textures to fit into that enticing 200MB bracket.

Using your file manager, navigate to: Android/obb/com.rockstargames.gtasa/