I should also consider if installing via APK and OBB separately changes the performance. The app store's method ensures all the files are correctly installed and verified. If the user side-loads the APK without the OBB, the game might not function correctly, or if they do get the OBB, the performance depends on the device's hardware rather than how they obtained the files.
Also, I should check if Modern Combat 3: Fallen Nation is still available. I remember that some games get removed from stores, but I'm not sure about this one. If it's not available, the user might be trying to find an older version, which complicates things further due to licensing and security concerns. download modern combat 3 fallen nation obb c better
I know that most Android games on the Play Store have a primary APK and then an OBB. The OBB is usually necessary for the game to run because it contains large media files like textures, soundtracks, etc. If the user installed the APK separately without the OBB, the game might not work properly. So, maybe the user is looking for an alternative way to get the OBB if the Play Store isn't working for them. I should also consider if installing via APK