You can still open unsigned apps with Gatekeeper on, you have to go into Settings to whitelist it. I find this extremely annoying, but as I said, that's the poi

You can still open unsigned apps with Gatekeeper on, you have to go into Settings to whitelist it. I find this extremely annoying, but as I said, that's the point of Gatekeeper, if you don't like it then turn Gatekeeper off.