If I needed to build a quick app that I would feel extremely confident with, I would launch a Digital Ocean droplet running Ubuntu or similar and set up Nginx /

If I needed to build a quick app that I would feel extremely confident with, I would launch a Digital Ocean droplet running Ubuntu or similar and set up Nginx / MySQL / PHP. I would use Lumen (~Laravel light) to build the API, probably using JSON web tokens for authentication. For the front-end, I would spin up a Redux-less Polymer build (web components) with a service worker. That would probably be my go-to stack, because I know it very well and can develop rapidly in that context.