Heroku is just a layer on top of AWS. I know a ton of successful business applications who rely on Heroku + AWS. Obviously after a certain size you will want t

Heroku is just a layer on top of AWS. I know a ton of successful business applications who rely on Heroku + AWS. Obviously after a certain size you will want to customize your hardware more, but in the early stages Heroku can take you a very far way. Ello is a recent app that had to scale to millions of users extremely quickly and did on Heroku. Read their technical write up: http://mikepackdev.com/blog_posts/40-5-early-lessons-from-rapid-high-availability-scaling-with-rails http://mikepackdev.com/blog_posts/40-5-early-lessons-from-ra... Ello had issues, and Heroku would be considered amateur for what they were doing, but if you read it Heroku was not the cause of their performance issues -- their application code was. IMO most business applications run into problems due to performance issues within their application code, not because of server downtime. Regarding how common downtime on Heroku is... yes, Heroku has lots of minor incidents impairing its toolkit and some services, but these are not issues that go notices. Two years in I still haven't had significant downtime from Heroku itself (more than 5 minutes) during business hours where it matters. Cloudflare, and other DNS providers, have frankly given me more trouble.