Accessing my node.js by others?

I have successfully launched my node.js server, and can access it through http://localhost:3000

How do I allow others see my development server? I do not have external IP.

For quick sharing in development stage there is a special NPM module called localtunnel. Do not use this method in production website due to security concerns.

Using localtunnel after you installed it (npm install -g localtunnel):

lt --port 3000

It shall output you the externally accessible URL after running the command, share this url with your friends.