After installing the APK, extract the OBB file (which usually comes in a ZIP or RAR archive) and move it to the correct directory on your device. The OBB file should be placed in the Android/obb/com.rockstargames.gtasa directory. If the directory doesn't exist, create it manually.
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Uninstall the standard version and install the CLEO-compatible APK . Download Gta San Andreas Apk Obb Mod Cleo
CLEO mods are generally safe if downloaded from modding forums. However: After installing the APK, extract the OBB file