If it’s built into the wall, it’s harder for a hacker to be able to intercept or do anything with a phone that is charging in those instances. In public places where there are devices sitting out and a place for people to plug in, you need to be cautious. A lot of times hackers will replace those devices with their own devices which look just like something that you can plug in to charge your phone and they actually infect your phone or computer with a virus as soon as you plug it in. It’s not super common, but you do need to be careful. It’s something that’s becoming a little more common at times. My recommendation is to not plug your USB cord into any charger port in a public place. It’s safe if you’re going to use your own charger that you plug into an outlet in a public place. That’s just power and can’t be hacked. Always bring your charger with you and plug in with that. Those USB ports can be dangerous.