Well, this is not really a mod Apk per se. More like, it does what you want it to do in the game. For example, you can change your car into any other car that is already in the game (not including special vehicles). This way, you could obtain vehicles like Lamborghinis without having to buy them with real money or obtain insane credits for every race completed.
There are more features planned by its developer and community, of course, but these things can’t be shared due to legal matters. Check out the bottom part below for links where you can get the free download of Among Us.