On what do I run my Node.js API so that my other machines can access it?

I have several apps running on AWS machines that need to access my Node.js API. I was wondering where I should run my API so that these machines can constantly make requests to the API.

On all of the tutorials that I have gone through, the API is run off of localhost, which is adequate for testing but not for production.

What do other people in the industry use to run their API's? Small scale? Large scale? I was thinking of just running it off an AWS Ec2 and having other apps make calls to the public DNS: port number of the API.