I list two different ways below.

  1. rails s --binding=
  2. localtunnel npm package

For the first method, simply run up rails server by this command, then access our server through your local machine public ip address with port 3000(by default). If you don't have a public ip address(only LAN address), you might need to configure your Router NAT to make port 3000 public visible.

The other way is using localtunnel npm package, you can install it by:

npm i localtunnel -g

After run up rails server(rails s), run

lt –port 3000

The localtunnel will give you an unique url, something like https://gqgh.localtunnel.me. Now you can share this url with people who want to access your local server.