WiFi. I got a brand new router because my other one died. I cannot get anything to reconnect except for my Google hub. Everything else will not connect. I have uninstalled the app and I have restarted all devices. I have unplugged everything. So far this is the worst experience, because now when I'm working in my office and my house is cold, I can't tell Google to warm up my house to 70ﾟ I have to walk downstairs and manually set it. That's not the point to a smart home.