As an update, I’ve followed the directions here https://www.digitalocean.com/community/questions/how-to-access-my-app-via-ip-without-specify-port to no avail.

Did you setup the subdomain for your app with the domains plugin?

# where `myapp` is the name of your app

# add a domain to an app
dokku domains:add myapp example.com

# list custom domains for app
dokku domains myapp

# clear all custom domains for app
dokku domains:clear myapp

# remove a custom domain from app
dokku domains:remove myapp example.com

With a little finagling in /etc/nginx/nginx.conf I was able to get to the “Welcome to nginx” page using subdomain.ourdomain.com but I’m not able to get to the point where I can access my application.