PM2
Node.js Production Process Manager with a built-in Load Balancer
...PM2 lets you manage, maintain and increase Node.js performance. It is constantly assailed by over 1800 tests so you can deliver high quality applications, and deploy confidently and more often.
PM2 is cross-platform and arguably the most widely-used process manager for Node.js with over 100 million downloads. Setting it up is easy, it just takes a couple of minutes and one simple command.