Following their basic tutorial, I deployed an example app in seconds. Then after creating a CNAME record for a subdomain, I linked the two together, and had my subdomain live with a valid Let’s Encrypt certificate installed and ready.
Everything about working with Now is very refined and the essence of simplicity – from their CLI, to their password-less logins and modern, minimalist account interface. It feels light-years ahead of any other hosting and deployment tooling I’ve played with. (Note that mapping custom domains is part of their Premium plan, but they also provide a free OSS Plan that allows more human-readable URLs than those generated by default.)