Using Tor on a smartphone mainly helps with privacy, not device security
This is just a direct answer and that is what it is. TOR is to protect one's privacy like hiding IP addresses while surfing on the internet, so it doesn't actually guarantee that one's smartphone cannot be hacked which is the compromise that OP is talking about if am not mistaken.
If you want your smartphone to be protected from hacking, then you need to learn about some developer's options that you can set from your smartphone which can reduce its vulnerability to hacks and attacks from scammers.
