Against the 5$ vulnerability, if you are that important, go for a gun permit and train on pigs so in a real life situation you wouldn't freeze.
Despite some popular fantasies, buying a handgun and shooting some targets (or live pigs?!?!) does not turn one into an action hero. That kind of escalation is likely to get the phone owner or another innocent person killed. It's a stupid risk, especially given that there are much better ways to protect your phone data.