Phone's apps are sandboxed, there are few cases (if any) of a wallet being compromised on the phone from the internet... Not the case with much less secure computers...

If you're running Samourai Wallet, no need for a hardware wallet imo... A spare phone can be kept offline and sentinel can be run hot from your primary device. Many ways to skin the cat.

https://ungovernablemisfits.com/podcast/exploring-sentinel/