Nothing if ABSOLUTLY free in this world. You just trade/change time for money, or money for hapiness, or risk versus stability, etc.
BTW, is bad practice/advice to blindly download/install something from internet, just because is "free", or you saw a youtube video about it, or a (not qualified in that field) "friend" recomended it. After you will be hijacked, randsome-ware, device became a brick etc, you have no one to complain.
If you have a spare/old device that you aford to distroy, then by all means knock yourself up. Play the ruSSian rulete. Or at least try in a simulator, not on a real device. YMMV.